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 Page 1 of 2 12
Username Post: Extremely rough running at idle.        (Topic#354156)
Smallen96 
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Posts: 18

Reg: 11-13-18
11-30-18 08:18 PM - Post#2752954    

Hey all, I have a 95 C1500 Pickup 5.7L TBI, it's my first time posting on the site and after a ton of searching I can't seem to find a solution. I have an extremely rough running truck when both hot and cold idling. I have to date replaced the 02, MAP, IAC, Intake gasket, Rebuilt the tbi with new fuel regulator assembly, Coolant sensor, Tested the condition with a computer I pulled off a donor, same result, replaced the distributor, ignition module, ignition coil, timing chain and gears,set the timing and replaced all the spark plugs and wires. Not all the parts listed were replaced for the symptoms and I realize that throwing parts at the problem is a terrible idea, so I decided to get a cable to hook up to my laptop to check the data with TunerPro RT, which hasn't helped at all because I don't know what to look for except I noticed it stalled directly after entering closed loop. The thing is when the truck has the ESC bypass unplugged, it runs really well, but when I cut it off and plug it back in, It runs terribly and eventually stalls, which leads me to believe that it's an electrical issue. I wish I could put up the .xdl file so a more knowledgeable mind could help me out. I did feel that the reading on the O2 sensor is off because it's reading around 900 to 1000 mV and it seems to jump from open to closed loop as it surges/lopes.





 
marsmann 
Poster
Posts: 11

Reg: 10-25-18
11-30-18 09:48 PM - Post#2752960    
    In response to Smallen96

When you connected your diagnostic tool to the obd1 system, were there any errors captured?

Regarding the 02 readings: Normal 02 operation should swing constantly, after it is warm and up to temps, between 100mV - 900mV (0.10 to 0.90V). If it stays constantly at 900-1000 without swinging it indicates a faulty sensor or a very rich condition, which in turn will send signals to the computer to lean the truck out. I know you replaced it recently, but many parts are junk out of the box these days.

Use the Tuner software to help isolate other readings such as the CTS temps, IAC counts, and even the TPS voltage. To help with interpreting the data you are looking at here is what you want to see at a high level:

CTS = 42 degrees or so when cold, and eventually rising to the 165-210 degrees when warmed up.

IAC counts = 20-50 is the normal ideal range. The closer to 20 the better on warm idle.

TPS = .5 volt to 1.25 volts at idle, and increase smoothly as you slowly open the throttle to at least 4 volts at wide open throttle. Make sure there are no dead or flat spots.

if you can post your map and other readings that would help, along with your BLMs, etc.

Right now it sounds "electrical" since you stated the truck idles normal with the ESC (advance) disconnected. Although I am somewhat confused since you also mentioned it runs rough on cold idle as well (which when cold the computer is open loop and not using sensory input - it runs on default tables and fuel curves). We are assuming for the moment the engine internals are in order and there are no valve adjustments or other mechanical issues out of order. We are also assuming timing is set to 0* with ESC disconnected.

Finally, on the surging between open/closed loop that is normal to an extent when just parked at idle. Anything under 165* or so can trigger open loop so if your thermostat is the normal 195 but the temps hover between the lower and higher range you can see the system constantly move in and out of open/closed loops (which can make it difficult to troubleshoot at times).



Edited by marsmann on 11-30-18 09:53 PM. Reason for edit: No reason given.

 
Shepherd 
Frequent Contributor
Posts: 1551

Loc: Lake George, NY
Reg: 11-11-15
12-01-18 05:30 AM - Post#2752969    
    In response to marsmann

Great info! I had that basic truck and had egr problems that caused surging and rough idle. A bad injector that is dumping fuel could cause the poor engine performance. Can we assume the engine is solid, has appropriate compression in all cylinders?



Edited by Shepherd on 12-01-18 05:32 AM. Reason for edit: No reason given.

 
Smallen96 
Poster
Posts: 18

Reg: 11-13-18
12-01-18 06:40 AM - Post#2752978    
    In response to marsmann

I apologize, I should have stated that no trouble codes popped up except last year when it was an 02 code, which is why I initially replaced that and the Code 42 for ingition error because of the unplugged bypass. As for isolating sensors, the cable I got said it doesn't have any tuning capabilities, just diagnostics. As for the diagnostic readings on cold start up while it's surging/loping, IAC present motor position jumps from 105 to 130, Coolant temp is 6.5, O2 voltage at 850-1000mV, Inj DC% jumps anywhere from 4-20, Injector base pulse width jumps from 2.5-5, TPS values seem to be fine, and the acceleration enrichment goes in and out as it lopes. All this is during open loop. If you need some warm diagnostics I can get those to you pretty easy.



 
Smallen96 
Poster
Posts: 18

Reg: 11-13-18
12-01-18 08:22 AM - Post#2752984    
    In response to Shepherd

i would say that's a solid assumption, I checked a few of the cylinder's compression and they checked out okay. Also the EGR and solenoid has been replaced, so many parts it's hard to keep track. The injectors seem to have a good spray, no dripping, so I don't think they're clogged. Some other info that may be helpful is that It does clear up for a bit after 1-3 minutes before intermittently doing it again, which i'm guessing is from the closed loop, or stalling at a stop light, which is also intermittent. The thing I hate is that it very well could be a part I've already replaced, but it's hard for me to tell which part.



 
Shepherd 
Frequent Contributor
Posts: 1551

Loc: Lake George, NY
Reg: 11-11-15
12-01-18 10:33 AM - Post#2752997    
    In response to Smallen96

That is why you try to eliminate guess work, and/or do one thing at a time to try and isolate the issue. Obd1 can be tough to find deeper problems, experience and seat of the pants come into play, still a stuck egr can contribute to the problem. Does it stumble or misfire on hard acceleration?



 
Smallen96 
Poster
Posts: 18

Reg: 11-13-18
12-01-18 11:36 AM - Post#2753005    
    In response to Shepherd

No, it runs fantastic under hard acceleration, but I did check the new EGR with a vacuum gauge and it seemed so release the pressure, not immediately, but faster than I thought it should, but I read that some EGR valves are made that way, and I couldn't find any info relating to that. But I did take some more readings and when everything levels out in open loop, everything is spot on with the information given except for the O2, which won't go lower than 500-600mV. But as soon as it hits open loop after about 10 seconds the condition comes back and it always eventually stalls within 3 minutes and the IAC jumps around once it starts up again. Also the block learn multiplier went as low as 106 before stalling



 
marsmann 
Poster
Posts: 11

Reg: 10-25-18
12-01-18 12:06 PM - Post#2753006    
    In response to Smallen96

  • Smallen96 Said:
....Also the block learn multiplier went as low as 106 before stalling



A couple of thoughts:

Ideal BLM should hover around 128 or so plus or minus 10. 106 is really low, indicating a rich condition and would correlate with the 02 readings above 800 regularly.

the intermittent stalling is probably the IAC moving in and out and causing your idle to drop to the point it stalls. It is best on these trucks to use delco or quality parts. Some of the generic parts don't work so well. Not sure what brand IAC you put it. But, an Idle valve that moves in and out can also be caused by a vacuum leak. Make sure the base gasket of the tbi you rebuilt does not have any vacuum leaks and check the truck throughout.

It is possible that your sensors aren't behaving or getting clean voltage if your grounds are not good. I would recommend verifying all of your grounds (the one from battery to fender, rear of engine to firewall, the one on the pass side to the frame near the starter, and especially the one that goes to the thermostat housing). Those grounds are important to the sensors.

If you happen to be near the south eastern PA area, I'd be happy to help you work on this (I'm not a shop looking to charge, just a dude looking to help).




 
Smallen96 
Poster
Posts: 18

Reg: 11-13-18
12-01-18 03:43 PM - Post#2753021    
    In response to marsmann

I wish I was in south east PA so you could help me out, I've been dealing with this problem for 3 years now, just slowly working on the truck when I have time, but I'm in east NC, so that's a no go, I appreciate the offer. Ill get back with you after I check and clean all the grounds listed. I have checked and rechecked for vacuum leaks countless times with various methods to no avail and tested the intake vacuum an it checks out at 19 inHg at idle when it's smoothed out. But it will probably be next week when exams are over before I can really dig in and do a thorough check.



 
marsmann 
Poster
Posts: 11

Reg: 10-25-18
12-02-18 04:48 PM - Post#2753127    
    In response to Smallen96

If your mercury is reading 19hg and steady that will indicate a healthy motor. so no need to worry about valves, etc. at that point.

Yes. It can be very frustrating. It sounds like you have one of those rarer situations that are harder to fix than usual. What you will find is that you will need to go through several rounds of looking at all of the same things over and over until you get lucky and get the right sequence.

I've worked on similar trucks before....

We will be here.



 
Smallen96 
Poster
Posts: 18

Reg: 11-13-18
12-03-18 09:20 AM - Post#2753182    
    In response to marsmann

Again, sorry, I have some information that I didn't put initially when giving all the data info. I see that the knock counts are what I believe to be extremely high from 400-10000, but the knock retard is 0, but I'll recheck the knock sensors resistance and be sure it's fine. Here is a link where I uploaded my data to youtube so you guys could take a look. The first part quarter is open loop rough running, the second quarter is open loop steady running, and the last half is closed loop rough running. right after then end of the video the truck stalled. https://youtu.be/YRnKb6tH1bY



 
someotherguy 
Senior Moderator
Posts: 28799
someotherguy
Age: 48
Loc: Texas
Reg: 08-01-03
12-03-18 10:33 AM - Post#2753195    
    In response to Smallen96

Super high knock counts with no knock retard is suspicious behavior. It kind of makes me question the validity of the data, though I've only worked with watching that kind of data a little bit while I was experimenting with slight base timing bumps (which turned out to be counterproductive; factory spec works best, at least in a stock setup/tune.)

Richard

06 Silverado ISS / 06 Silverado SS / 06 300C SRT8


 
Smallen96 
Poster
Posts: 18

Reg: 11-13-18
12-04-18 03:44 PM - Post#2753376    
    In response to someotherguy

I thought it was suspicious also, so I went to checking different sensors to make sure the information is correct, and so far I've checked the MAP, IAC, TPS, Injector Resistance, EGR valve and Knock sensor, which all tested fine with a multimeter. I also checked and cleaned most of the major ground connections that marsmann stated. I can't find any information on how to test the O2 sensor or the purge solenoid. I plan to test the ignition parts (pick-up coil, ICM, and coil) and for a vacuum leak (for the 50th time) in the next 2 days, so I'll post an update when I do that.



 
marsmann 
Poster
Posts: 11

Reg: 10-25-18
12-04-18 07:48 PM - Post#2753410    
    In response to Smallen96

  • Smallen96 Said:
Again, sorry, I have some information that I didn't put initially when giving all the data info. I see that the knock counts are what I believe to be extremely high from 400-10000, but the knock retard is 0, but I'll recheck the knock sensors resistance and be sure it's fine. Here is a link where I uploaded my data to youtube so you guys could take a look. The first part quarter is open loop rough running, the second quarter is open loop steady running, and the last half is closed loop rough running. right after then end of the video the truck stalled. https://youtu.be/YRnKb6tH1bY



It's a shame it stalled at the end. I did see in the video there were slight milliseconds where the IAC dropped under 10 and into single digits. So I can see why it stalled.

I noticed a couple of things that seemed odd, or we need to verify. So the following is just quick random stuff going through my head after watching the video.

1. Your battery voltage was only showing like 13.3 while running. This is low. We would want to see 13.5 and ideally over 14 up to 14.6 usually while running. Especially at fast idle and at the rpms your video shows. Why is this important? Because we have seen with these trucks that they have a sensitivity with voltage to the sensors that can be caused by faulty alternators or bad batteries. Either can cause strange electrical anomalies and poor rough/running conditions.

2. Knock retard at 0 = very strange. Poor man's method of testing the knock sensor is to get her idling as smooth as you can, spot a timing light at the crank and tap the block on the passenger side with a small hammer (no need to whack hard) and see if the idle jumps. I'm not sure if your tool is reading this right (hopefully you are using the proper PROM ID for your trucks computer) but if the sensor is bad, or possibly even disconnected (I have seen this before when shops replace the starter and don't connect the knock sensor). If you do the test above at least you can tell if the sensor works or not. This problem, however, will not affect your idling.

3. Your engine temperature never really went above 165* before stalling so it technically should still be in open loop (cold start default tables). I also don't think your 02 sensors are getting up enough to temps to switch you over to closed loop.

4. TPS and Map (Kpa) look normal to me at these values. TPS would be nice to see it closer to .58-.60 instead of just .5 but not sure if the tools just shows this differently. I dont use tuner pro.

In case I missed this before, your truck is stock right? Meaning you aren't trying to use a default tune on something like a modded cam or anything are you? It's important for us to assist in troubleshooting to establish these baselines...

And does your IAC have a gasket? Normally the surface should be flat enough but they do come with gaskets for a better seal...





 
someotherguy 
Senior Moderator
Posts: 28799
someotherguy
Age: 48
Loc: Texas
Reg: 08-01-03
12-04-18 09:05 PM - Post#2753418    
    In response to marsmann

100% agreed on the voltage, and I've seen odd behavior as well with a weak battery - had one with a dead cell that would still start but sometimes needed a boost; it had a big flat spot off idle. New battery solved it. At any rate with a good charging system I would expect very near 14.1 running with accessories off.

Testing the knock sensor by tapping on the engine may not work in his case unless it's in gear. I forget the specifics but some years this test will not show any results with it in park; I think the dividing line is ECM vs. PCM years so if his '95 is an automatic...

You did jar my memory with that comment about the sensor simply not being connected. I do know in the case of newer systems, for example a 1996 Vortec, if the knock sensors (2 on the Vortec 7.4) are not connected, the PCM assumes worst case scenario and you will see lots of knock counts although they're not even connected! It's sort of a protection effort to pull back some timing in the event there's any knocking that can't be detected because the sensors are not reporting.

Richard

06 Silverado ISS / 06 Silverado SS / 06 300C SRT8


 
65_Impala 
Very Senior Member
Posts: 4139

Reg: 12-29-02
12-04-18 09:07 PM - Post#2753419    
    In response to Smallen96

I missed seeing this before, but your O2 readings certainly are wrong for closed loop. They should fluctuate from around the 0.3V range to 0.8V range. At any rate, constantly going above and below 0.45V. I would suspect the PCM is pulling fuel and making the engine run lean.

Try unplugging the O2. The computer should read about 0.5V and it should throw an O2 code when it tries to go closed loop. It's definitely something with your O2 if the operation immediately clears up once the code is thrown.

Knock counts like that are fine. They constantly go up. You can get a couple of 1000 just starting it. It only actually retards the timing when the count is rising.



 
Smallen96 
Poster
Posts: 18

Reg: 11-13-18
12-05-18 04:32 AM - Post#2753438    
    In response to marsmann

To answer your questions in order

1. I had a glove box light that wouldn't shut off that I found and unplugged yesterday, so the battery was a bit low, but I'll still check it out to be sure. With the latest runs, it's showing 13.6-13.7, which isn't ideal, but not as bad.

2. I tested the sensor and it was plugged in and it tests fine at 3300 ohms, but I will perform the test either today or tomorrow. My computer and PROM are stock, so I know it's the right one and the extension I'm using to read everything came off TunerPro RT's website, so I'm hoping it's reliable.

3.I didn't think about that, but my O2 sensor has 3 wires coming out of it, I'm not sure if that matters or if that means its heated or not.

4. I've never used this software before either, so I'm trying to make sure the values it's giving are correct or not. If you have any suggestions on software to use, I'm fine with switching. I wanted to use WINALDL, but they don't support my computer type, which is 16197427.

5. Yes, everything is completely stock as far as I'm aware, when it was first bought by my dad it ran perfectly fine and one day it just started acting up. Also the IAC does have a gasket.



 
65_Impala 
Very Senior Member
Posts: 4139

Reg: 12-29-02
12-05-18 10:30 AM - Post#2753483    
    In response to Smallen96

I watched your video again. It must be going closed loop. The Integrator starts moving and the Block Learn Multiplier starts dropping which both indicate it's in closed loop. I bet it runs worse as the BLM gets lower. The only problem I see is the bad O2 sensor readings.

So, you need to check the O2 sensor and wiring. Something is causing the O2 readings seen by the PCM to be completely messed up. The 3 wires on the sensor itself will be 2 the same color and 1 a different color. The 2 the same color are the heater. The 3rd wire is the O2 sensor output wire.

Here are some troubleshooting steps to take.


- Remove the sensor and use a torch to test it. Connect the meter set to DC voltage between the signal wire and the base of the sensor. https://www.youtube.com/watch?v=o6iXNBPPhwc

- Check for ignition power on those wires. Remove the sensor and check that it gets hot with the key on, engine not running.

- Check the wiring from the sensor to the PCM to ensure it's healthy with no damage.

- Run a ground wire from the sensor base to the intake, preferably the intake bolt where the PCM wires are grounded.


As for the other stuff like IAC and knock - quite worrying about them, they're not the problem.

The IAC operates inversely to the rpm error. When surging, I can clearly see the IAC close when the rpm rises and open when the rpm drops, which is perfectly normal. Near the end of the video, the desired idle rpm is 700. Any time the engine is above 700rpm, the IAC closes and any time it goes below 700rpm, the IAC opens. A similar thing happens to the timing advance. Both are attempting to stabilize the idle rpm, but can't because it is lean surging so badly.

The knock counts go up any time knock is detected. It's a register that will rise with detected knock until it reaches the maximum value the register can hold (which I can't recall offhand but maybe about 65000). Then, the register goes back to 0 and starts rising again. Actual timing knock retard has nothing to do with the absolute number in that register. There is a decision process that decides to retard the timing when the number is climbing based on how fast it's climbing. But it only does it under certain conditions. At idle, it likely doesn't do any timing retard.




 
Smallen96 
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Posts: 18

Reg: 11-13-18
12-05-18 12:19 PM - Post#2753494    
    In response to 65_Impala

Okay, that's great info. Yesterday I unplugged the O2 sensor and ran it for a bit, plugged it back in and the O2 sensor started cycling like its supposed to for about a minute or so before going back up. The truck seemed to run better when it was cycling, but of course went to normal once it settled back around 950mV. I will bench test it soon to be sure and clean off all connectors and trace the wiring to be sure in the next day or so, Ill let you know.



 
65_Impala 
Very Senior Member
Posts: 4139

Reg: 12-29-02
12-05-18 01:02 PM - Post#2753499    
    In response to Smallen96

It plugging it did that, then take a good look at the connector for damage and the wiring in that area for a damaged connector or wire breaks. Sometimes the female terminals in a connector open up so they don't make good contact.



 
Smallen96 
Poster
Posts: 18

Reg: 11-13-18
12-05-18 01:42 PM - Post#2753505    
    In response to 65_Impala

Just checked the sensor and it checks out fine on the bench, and all the wiring is fine. I also ran a ground from the body of the sensor to the intake all with no change in engine behavior. I also unplugged the sensor while it was running with no change in behavior and no trouble code popped up.. It also cycles fine when I accelerate, like when I keep my foot on the pedal and steady, I kept it in the 2000 range and it acted fine.



 
Smallen96 
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Posts: 18

Reg: 11-13-18
12-05-18 02:17 PM - Post#2753514    
    In response to 65_Impala

Okay, so I know for a fact that it is running rich because I just pulled 2 spark plugs (which was the first thing I replaced in this series of replacements), one on each side, and they looked like I spray painted them with black spray paint. Also, the exhaust smells a bit rich, but I'm not totally certain. I don't really care to inhale a bunch of exhaust fumes. So I'm not sure what to look at next. I plan to get some new plugs tomorrow and replace them Friday morning.



 
65_Impala 
Very Senior Member
Posts: 4139

Reg: 12-29-02
12-05-18 07:56 PM - Post#2753553    
    In response to Smallen96

If you're quite sure it's not the O2 sensor then it's getting too much fuel at idle. Maybe it's a bad or leaking injector. Look at the pattern. It should be a nice cone with no drips. Both sides should look the same. Sometimes using a timing light to look at the pattern helps make it clearer.

Have you checked the fuel pressure?



 
Smallen96 
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Posts: 18

Reg: 11-13-18
12-06-18 05:54 AM - Post#2753598    
    In response to 65_Impala

I'm not saying that the O2 sensor is totally ruled out, but after bench testing it, it seems to be okay. and the fuel injectors look like they have a cone shape with no dripping, but I'll see if I can't take a video tomorrow and post it. As for the fuel pressure, it tests at around 11-12 psi at idle and stays steady while the truck is surging. Could the ignition system cause a rich condition? I havent fully checked it yet, but maybe it's causing the surging, which maybe makes it to where it doesn't burn all the fuel?



 
marsmann 
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Posts: 11

Reg: 10-25-18
12-06-18 08:21 AM - Post#2753621    
    In response to 65_Impala

  • 65_Impala Said:
I watched your video again. It must be going closed loop. The Integrator starts moving and the Block Learn Multiplier starts dropping which both indicate it's in closed loop. I bet it runs worse as the BLM gets lower. The only problem I see is the bad O2 sensor readings....



I concur with this. I was looking at CTS readings and general temps but the BLMs would not drop until the computer took over to adjust for air/fuel based on 02 inputs.

The truck is definitely running rich. I know you have already eliminated egr and other issues but the evidence does point to too much fuel or an inbalance in the fuel system. It is way too rich.

The CTS and 02 are usually the two biggest culprits and your CTS appears to be fine. I would try the additional 02 sensor tests posted to see what happens.

Otherwise, I would begin inspecting the wires around the TBI itself. Sometimes little woodland creatures like to munch on rubber and you develop faults in the system.




 
Smallen96 
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Posts: 18

Reg: 11-13-18
12-06-18 10:35 AM - Post#2753631    
    In response to marsmann

I forgot to check for it heating with the key turned on, so I'll do that tomorrow when I change the plugs, but wouldn't a steady .9V cause a lean condition? I know it's really rich, but doesn't that coincide with the .9V reading? I'm not trying to be difficult, just trying to get a grasp of all the information. I'll also continue searching for the golden skinned/chewed wire that solves it all also.



 
marsmann 
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Posts: 11

Reg: 10-25-18
12-06-18 04:17 PM - Post#2753663    
    In response to Smallen96

  • Smallen96 Said:
I forgot to check for it heating with the key turned on, so I'll do that tomorrow when I change the plugs, but wouldn't a steady .9V cause a lean condition? I know it's really rich, but doesn't that coincide with the .9V reading? I'm not trying to be difficult, just trying to get a grasp of all the information. I'll also continue searching for the golden skinned/chewed wire that solves it all also.



Yes, the 02 sensors reading up that high all the time indicate faulty sensors or a rich condition. This information from the 02 sensor is what the computer will use to pull back fuel and then run lean.

Unless your 02 sensor is a 3-wire with heat, you will need the car running to bring them up to temp. I have seen 95 chevys with a simple sensor while the GMCs of the same year have 3 wire...





 
Smallen96 
Poster
Posts: 18

Reg: 11-13-18
12-06-18 04:21 PM - Post#2753664    
    In response to marsmann

Mine is a 3 wire, so I'll have to check to see if it heats on its own tomorrow. Ill also check all the ignition components to rule them out tomorrow.



 
CowboyTrukr 
"7th Year" Silver Supporting Member
Posts: 4093
CowboyTrukr
Loc: Salt Lake City
Reg: 06-20-09
12-06-18 07:10 PM - Post#2753685    
    In response to Smallen96

My ‘95 Chev has a 3 wire O2 sensor.

Greg

'95 K1500 Z71 EC Short Step 5.7L+0.040/NV3500
'00 Explorer XLT 4.0 V6 Auto
'94 K2500 5.7 NV4500 ECLB - SOLD
‘87 GMC S15 SCLB 4.3 Auto - SOLD

"The only thing necessary for evil to triumph is for good men to do nothing" Sir Edmund Burke


 
65_Impala 
Very Senior Member
Posts: 4139

Reg: 12-29-02
12-07-18 07:04 AM - Post#2753720    
    In response to Smallen96

  • Smallen96 Said:
I forgot to check for it heating with the key turned on, so I'll do that tomorrow when I change the plugs, but wouldn't a steady .9V cause a lean condition? I know it's really rich, but doesn't that coincide with the .9V reading? I'm not trying to be difficult, just trying to get a grasp of all the information. I'll also continue searching for the golden skinned/chewed wire that solves it all also.




Well, check the heater. I should have paid more attention to the fact you never specifically said you checked it.

I had a similar thing happen on a swap when I tried to leave the 1-wire in place instead of re-wiring for a heated O2. It worked great whenever the rpm was higher, like when driving, but as soon as the engine was idling the O2 would stick high and the engine would start to lean out and begin surging.

Your truck is refusing to throw an O2 error code. If it would, it'd go back to open loop and also quit using any of the BLM data which would help you troubleshoot the issue. I've seen it happen before, have even seen LS engines with their newer and more powerful PCM's not throw an O2 code when the O2 was acting up.



 
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