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Username Post: Info: "Truck won't start" checking spark and fuel pressure        (Topic#253427)
someotherguy 
Moderator
Posts: 25679
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
11-27-10 10:29 AM - Post#2010080    

People often come here looking for help because their truck won't start. Here's a couple of posts that will hopefully consolidate most of the advice our members have contributed, and I will add it to the FAQ posting at the top of this forum. If you have suggestions or corrections, please reply here with them and I'll update this post! The better the info, the better we're helping. Thanks!

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

NOTE: All of these suggestions make the assumption you have checked the basics. No blown fuses, plug wires in correct order, gas in tank, etc.

Throttle Body Injection (TBI) 1987-1995 (Vortec info in next post)

Checking for Spark:
A reliable and safe way is with an inline spark checker; I use Lisle #20610, about $10 and available at most good parts houses. It simply goes in-line between a plug wire and the plug itself. If you're doing this test without a helper, you can experiment with positions to install it so you can still watch it through the gap between the rear of the hood and the engine compartment.


If spark appears weak or erratic, remove the distributor cap to check inside it for moisture.
You can dry it out by spraying WD40 inside and wiping the excess out with a paper towel. If the cap has moisture, it is probably cracked or was not seated properly.

If no spark, suspect the ignition module.
The module is the black device inside the distributor under the rotor. Some parts houses can test them but the test isn't always reliable. If you replace the module, be sure to clean off the existing heat sink compound from the distributor base, then apply a thin but even layer to the new module. Heat sink compound should come with the new module but if not, you can get a small tube at Radio Shack. Dielectric grease isn't the same and won't work.

Before you replace the module, also check the pickup coil.
This is the round device between the rotor mounting pad and the ignition module. Unplug it from the module. Using an ohmmeter test the two pin connector; you should see 500-1500 ohms. Testing one pin to ground (distributor base) should read infinite resistance. If both are not true, replace the pickup coil. This requires removing and disassembling the distributor, or buying a new one. Also, sometimes the magnets in the assembly get weak (though they are not incredibly strong when good.)

If spark is good, move on to fuel pressure.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Checking fuel pressure:

NOTE: when you turn the key on, the ECM/PCM will prime the fuel system by running the pump for 2 seconds (30 if you have the "hot fuel module" which isn't that common.) If you don't start the engine, the pump will quit running. This can make it tricky to get a "key on" pressure reading by yourself, as the pressure can drop off before you get to read the gauge. Have a helper turn the key while you watch the gauge.

Do not assume the pump is working because you can hear it, or not working because you can't hear it. TBI pumps are usually very quiet. Also do not assume that because there is residual pressure when you disconnect the lines, that the pressure is good. It must be measured.

TBI V6 and V8 small block fuel pressure spec is 9~13 psi but I prefer to see at least 10 psi. TBI big block spec is the same for 87-93, but 94-95 is higher at 26~32 psi. I use a gauge set with a special adapter for testing TBI engines as TBI's don't come with a test port. The adapter can be used at the filter area, or a more permanent location behind the TBI (harder to install but easier to use for periodic monitoring; DO NOT leave gauge permanently attached!) A gauge without the adapter can be T'd in with two pieces of scrap 3/8" fuel line and a regular barbed T that comes with some gauge kits.

Pictures in order:
Actron #0180-000-1320 is the adapter fitting for testing TBI, sells for about $10 or less (though many places sell it far higher). Actron #CP7817 is a gauge kit that includes the adapter and sells for about $50~$60. Harbor Freight US General #92699 about $20, doesn't have a TBI adapter but can be T'd in with scrap hose as shown in last pic, by carefully pushing the hoses over the hard lines where the filter goes. Also note it does not have the pressure release valve the Actron has.




If your pressure is low or zero, before replacing the pump:
- If you haven't replaced the fuel filter recently, you should try this first.
- On the pump/sender assembly the short piece of hose joining the pump to the sender can crack or slip off.
- Fuel pressure regulator could be bad, though it's somewhat uncommon to happen on TBI engines. Replacement requires some TBI disassembly.
- Fuel pump fuse or relay could be bad; check the fuse (under the "convenience center" cover under hood); if it's blown the pump is likely bad or there is a short in the wiring. The pump relay on TBI engines doesn't go bad often.

If spark is good and fuel pressure is good, still suspect the ignition module. They can fail in a way that still allows spark but does not signal the ECM/PCM to fire the injectors.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

If you own a fuel injected vehicle and do your own repairs (or want to be sure you're keeping your mechanic honest) you really should own these basic diagnostic tools. For less than $100 you can be adequately equipped to do this basic, but necessary troubleshooting.

Richard

 
Low priced Genuine GM Auto Parts
someotherguy 
Moderator
Posts: 25679
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
11-27-10 10:37 AM - Post#2010083    
    In response to someotherguy

People often come here looking for help because their truck won't start. Here's a couple of posts that will hopefully consolidate most of the advice our members have contributed, and I will add it to the FAQ posting at the top of this forum. If you have suggestions or corrections, please reply here with them and I'll update this post! The better the info, the better we're helping. Thanks!

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

NOTE: All of these suggestions make the assumption you have checked the basics. No blown fuses, plug wires in correct order, gas in tank, etc.

Vortec injection 1996-up (TBI info in previous post)

Checking for Spark:
A reliable and safe way is with an inline spark checker; I use Lisle #20610, about $10 and available at most good parts houses. It simply goes in-line between a plug wire and the plug itself. If you're doing this test without a helper, you can experiment with positions to install it so you can still watch it through the gap between the rear of the hood and the engine compartment.


If spark appears weak or erratic, remove the distributor cap to check inside it for moisture.
You can dry it out by spraying WD40 inside and wiping the excess out with a paper towel. On the big block, you may need to remove the coil/module bracket from the rear of the plenum to access the distributor. If the cap has moisture, it is probably cracked or was not seated properly. Be VERY CAREFUL re-installing, as the Vortec distributor body is plastic and it's easy to damage the places where the screws thread in. If you buy a new cap, use your old screws as often the new ones have threadlocker that makes the screw "fat" and easier to break the distributor. If either or both cap mounting tabs are broken and you need to rig it to get by: the easiest/best method I have seen is to use a zip tie (chain them together if you don't have one long enough) looped under the distributor body around the cap, through the gap between the centermost terminals to keep it the tie from sliding off.

If no spark, suspect the ignition module.
The module is riveted to the coil bracket next to the coil. On the big block it's difficult to see as it's bolted to the rear of the plenum, above the distributor. If you want to try another temporarily as a test, try hooking it up and use a nice heavy ground wire w/clips to attach the body of the module to the module/coil bracket. As of this time I am not aware if the parts house can test a Vortec module.

If spark is good, move on to fuel pressure.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Checking fuel pressure:

NOTE: when you turn the key on, the PCM will prime the fuel system by running the pump for 2 seconds. If you don't start the engine, the pump will quit running. This can make it tricky to get a "key on" pressure reading by yourself, as the pressure can drop off before you get to read the gauge. Have a helper turn the key while you watch the gauge.

Do not assume the pump is working because you can hear it, or not working because you can't hear it. Vortec pumps are usually noisy, but it's not necessarily an indicator of condition. Also do not assume that because there is residual pressure when you disconnect the lines or depress the test valve, that the pressure is good. It must be measured.

Vortec small block spec is 60-66 psi. They are incredibly picky and generally won't start if it's a little low. You want to see at minimum 55 psi or so (varies.) Vortec big block spec is 58-62 psi. They will start on very low pressure, just run poorly. You want to see at minimum 50+ psi to run right.

If your pressure is low or zero, before replacing the pump:
- If you haven't replaced the fuel filter recently, you should try this first.
- Fuel pressure regulator could be bad, or poppet valves (small block) could be leaking. Replacement requires intake disassembly.
- Fuel pump fuse or relay could be bad; check the fuse and relay (under the "convenience center" cover under hood); if fuse is blown the pump is likely bad or there is a short in the wiring. The pump relay on Vortec engines is often a sore spot with burnt contacts and melted socket.
- On the fuel pump/sender assembly (old style, with separate pump mounted to sender) the short piece of hose or the pulsator unit joining the pump to the sender can crack or slip off.

Pictures in order:
Vortec small block test port is to the right of the black "Vortec" cover over the throttle body. Vortec big block port is right at the front of the plenum. Both should have a black plastic cap. Actron #CP7818, about $40. Harbor Freight US General #92699, about $20 will work, too. Note it does not have the pressure release valve the Actron has. *** I have recently read posts that said the Harbor Freight gauge is hit or miss on how well the hose fits the test port on the engine, so bear this in mind when buying cheap tools!




If spark is good and fuel pressure is good, still suspect the ignition module. They can fail in a way that still allows spark but does not signal the PCM to fire the injectors.
As of this time I am not 100% sure if this is true on the Vortec engines, or if the cam sensor inside the distributor signals the PCM to fire the injectors.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

If you own a fuel injected vehicle and do your own repairs (or want to be sure you're keeping your mechanic honest) you really should own these basic diagnostic tools. For less than $100 you can be adequately equipped to do this basic, but necessary troubleshooting.

Richard
94 C2500LD / 94 C1500 / 06 300C SRT8 .. and an LS-swapped 97 Suburban
Check out my truck shop projects


 
JJR 
Senior Member
Posts: 227

Loc: Leesburg, GA USA
Reg: 10-12-00
11-27-10 02:54 PM - Post#2010165    
    In response to someotherguy

Funny you should post this today, I'm going thru the "truck won't start" problem on my 99 C2500 Crew Cab (88-98 body style) 5.7 vortec. I have the Harbor Fieght fuel pressure gauge you show (got it last Christmas on sale for $9.99) but I use my timing light to see if I'm getting spark (might have to get the Lisle tool). After doing some playing, it appears my fuel pressure after the truck has been sitting a while is just shy of 50 psi in the key on position and the truck won't start but if you turn the key on/off several cycles and get the fuel pressure above 50 psi, the truck starts but the pressure stays around 50 psi. When you shut the truck off, the fuel pressure jumps to around 60 psi and the truck will immediately re-crank. I shut it off and came back about 20 minutes later and the pressure gauge read about 30 psi but when I turned the key the pressure went above 50 psi and it cranked right up. I have changed the fuel filter as you recommended but now I'm a little stumped. Do you think the fuel pressure regulator is whats causing my issue?

 
someotherguy 
Moderator
Posts: 25679
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
11-27-10 03:00 PM - Post#2010171    
    In response to JJR

Regulator or leaky poppet valves. Could also just be a marginal pump. Tough call on that one because the integrated style on your '99 is expensive, and I suggest only getting the AC Delco or Delphi. The cheaper ones (Airtex especially) are horrible.

Richard
94 C2500LD / 94 C1500 / 06 300C SRT8 .. and an LS-swapped 97 Suburban
Check out my truck shop projects


 
JJR 
Senior Member
Posts: 227

Loc: Leesburg, GA USA
Reg: 10-12-00
11-27-10 03:31 PM - Post#2010181    
    In response to someotherguy

Being a newbie to major Vortec maintenance, can the upper portion of the intake be removed without replacing/removing the lower portion of the intake and the distributor? (ie: will the lower portion of the intake still be "bolted" down to the heads when you pull the upper intake?)I had the intake gaskets replaced a little over a year ago (should have done it myself but was leary of getting the distributor back in the exact position).

 
someotherguy 
Moderator
Posts: 25679
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
11-27-10 04:07 PM - Post#2010194    
    In response to JJR

Yep; the halves split apart - plastic off the lower aluminum piece. That's how you access the regulator and injectors. The distributor goes through the lower aluminum part; you only need to remove it if you were doing intake gaskets or something like that.

Remove fuel lines, move a couple small accessories and hoses out of the way, all the small bolts/studs out of the plastic portion of the intake will lift off. It can be tight because of the o-ring sealing the intake in the center around the injector unit. If it really doesn't want to budge, look around and sure you didn't miss anything.

There are better explanations of this all through the forum, some with pictures I think; if you can't find them with a search - check the FAQ post about improving how you use the search function.

Richard
94 C2500LD / 94 C1500 / 06 300C SRT8 .. and an LS-swapped 97 Suburban
Check out my truck shop projects


 
JJR 
Senior Member
Posts: 227

Loc: Leesburg, GA USA
Reg: 10-12-00
11-27-10 04:23 PM - Post#2010205    
    In response to someotherguy

Thanks. I was hoping that was the case. I have the GM service manuals for my 99 Express Van but have not slurged to get them for the truck (still have my 93 factory manuals from owning a 93 GMC). Looks like the Vortec Engine info would be basically the same for a truck and van so I should have what I need. Guess I will go for replacing the regulator and go from there. Like I mentioned when the truck runs the fuel pressure stays at 50 psi but it should be more like 60 psi. Is that correct?

 
someotherguy 
Moderator
Posts: 25679
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
11-27-10 04:28 PM - Post#2010209    
    In response to JJR

Yes, the engine in the '99 van would be the same as the '99 C2500; providing they're both small block V8's - so you can use the van service manual at least for most of the engine work.

50 psi is too low. You want a minimum of 55+, the closer to around 60 the better. You can attempt to clamp off the rubber portion of the return line under the truck, use vise grips and a folded-over piece of tin or thick plastic to protect the rubber, and experiment with the tightness so you don't kill the hose. Have someone turn the key on, pause, then start it for a moment while you watch the gauge. If it bounces up much higher, then the pump is probably OK; suspect is regulator or leaking poppets. Don't run it like this; just long enough to see the gauge.

Richard
94 C2500LD / 94 C1500 / 06 300C SRT8 .. and an LS-swapped 97 Suburban
Check out my truck shop projects


 
JJR 
Senior Member
Posts: 227

Loc: Leesburg, GA USA
Reg: 10-12-00
11-27-10 04:33 PM - Post#2010212    
    In response to someotherguy

Thanks for the tip. I will try it tomorrow.

 
Chevytech 
Subject Matter Expert - Senior Member
Posts: 2998

Loc: Twin Cities, Minnesota, U...
Reg: 04-25-04
11-27-10 05:22 PM - Post#2010241    
    In response to someotherguy

Hi Richard,

On your fuel pressure information you should mention that the pump only runs a few seconds when the key is turned on without cranking the engine. Many people assume the pump should run whenever the key is on.

You may want to mention the redundant circuits suppling power to the fuel pump, but that may confuse some people.
For those of you that are wondering why you are not getting replies to your thread:

Did you give the model, year, engine, fuel system type, and transmission information?

If the it has been altered from stock let us know about that too.


 
someotherguy 
Moderator
Posts: 25679
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
11-27-10 05:25 PM - Post#2010244    
    In response to Chevytech

Excellent suggestion! It's hard for me to remember all the details when trying to hammer one of those posts out. I had meant to do a quickie and 1.5hrs later found myself still editing...

I'll add the pump priming info and consider how to word the pump circuit info as to not have it be ridiculous (if that's possible.)

I tried to write something quick and simple; go too long and people won't read it. Somehow I still wrote a mini-novel.

Richard
94 C2500LD / 94 C1500 / 06 300C SRT8 .. and an LS-swapped 97 Suburban
Check out my truck shop projects


 
Durby 
Forum Newbie
Posts: 31

Loc: Oroville, CA
Reg: 10-30-10
12-11-10 09:52 PM - Post#2016779    
    In response to someotherguy

My wifes 97 2 wheel drive just started doing this. Turn the key and the trucks acts like its gonna fire then doesn't. Kinda like spark on 1 plug but no others. I have not checked fuel pressure as of yet but will do that. The truck normally starts after after a few minutes of key off then on short crank key off then on short crank. Cold morning seem to be the worst. The spark looks very weak when compared to the spark in my 92 4x4. Both trucks have the 4.3ltr engine in them the 97 is the Vortec.

Of note, the truck only has 137k miles on it and I have only replaced the plugs 1x. I have never tried replacing the cap or anything else. Once it starts though, it will run great and fire right up until the next morning.

 
Auzivision 
Forum Newbie
Posts: 57
Auzivision
Reg: 01-11-11
01-25-11 03:09 PM - Post#2037166    
    In response to Durby

I know the Acton 7817 comes with the TBI adapter and the 7818 doe not, but I hoping to find one that is more compatible with newer engines too. Does this set (Acton 7838) contain the right connector for TBI testing?
http://www.amazon.com/Actron-CP7838-Profess ional-P...

I'd like to add one of these to my tool box and prefer to only do it once if possible. Also, can the test port remain in a TBI system or do you have to take it in and out for testing?
1992 GMC C1500 Sierra SLE w/ 5.7L T.B.I


 
someotherguy 
Moderator
Posts: 25679
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
01-25-11 05:35 PM - Post#2037230    
    In response to Auzivision

That 7838 does come with the TBI adapter; it's the banjo-bolt looking item near the bottom left of the pic, next to the T.

You can leave the fitting in place, regardless of if you put it up by the TBI, or down by the filter. You will need to rearrange the fuel line slightly so it can fit. It can be a bit of a PITA but you only have to do it once.

Do yourself a favor on the permanent install; grab a port cap so dirt doesn't get in. Same cap is used on Vortec test ports; that's the kind I pirated for mine.

Richard
94 C2500LD / 94 C1500 / 06 300C SRT8 .. and an LS-swapped 97 Suburban
Check out my truck shop projects


 
Auzivision 
Forum Newbie
Posts: 57
Auzivision
Reg: 01-11-11
01-25-11 07:23 PM - Post#2037296    
    In response to someotherguy

Thanks again Richard, you are always on the mark. I'm thinking I want to install the test port at the TBI for a couple reasons. One being so I can practice some before and after tests while replacing this old bugger:



Plus easier access and less dirt under the hood, I think. What is the reasoning for installing by filter… is it easier?
1992 GMC C1500 Sierra SLE w/ 5.7L T.B.I


 
someotherguy 
Moderator
Posts: 25679
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
01-25-11 07:25 PM - Post#2037297    
    In response to Auzivision

Much easier. I put mine up by the TBI though since my truck is very low; it would be a major pain to climb under and hook up the gauge, read, or remove it.

The hassle of putting it up by the TBI is you have to remove the bracket at the transmission bellhousing bolt that holds the hard lines, so you can get enough slack to push the supply line back to fit the adapter in there. It's tricky. Prepare your list of favorite cuss words...and be 100% sure the new position of the lines isn't allowing them to rub on anything.

Richard
94 C2500LD / 94 C1500 / 06 300C SRT8 .. and an LS-swapped 97 Suburban
Check out my truck shop projects


 
88S10SPORT 
Forum Newbie
Posts: 10

Reg: 04-05-11
04-06-11 01:04 PM - Post#2072768    
    In response to someotherguy

hello, I am new to this website and american cars in general. I'm working on a 97 chevy k2500hd with the 5.7l vortec.

I had a question about checking the fuel pressure on it. You say after the key is switched on, the pump runs for 2 seconds then if its not started quits. When the pump quits, does pressure drop straight to zero?

I'm asking because I'm trying to diagnose a no-start issue that is happening to the truck I'm working on, and my friend doesn't believe its supposed to do that.

A little bit of clarification on if the pressure drops right away, or if the pressure slowly drops off would be very helpful to me. Thanks!

 
355Cheyenne 
Senior Member
Posts: 3765
355Cheyenne
Loc: Northern MN
Reg: 10-27-04
04-06-11 02:24 PM - Post#2072793    
    In response to 88S10SPORT

  • 88S10SPORT Said:
hello, I am new to this website and american cars in general. I'm working on a 97 chevy k2500hd with the 5.7l vortec.

I had a question about checking the fuel pressure on it. You say after the key is switched on, the pump runs for 2 seconds then if its not started quits. When the pump quits, does pressure drop straight to zero?

I'm asking because I'm trying to diagnose a no-start issue that is happening to the truck I'm working on, and my friend doesn't believe its supposed to do that.

A little bit of clarification on if the pressure drops right away, or if the pressure slowly drops off would be very helpful to me. Thanks!



Hello and welcome to the forum. First I would suggest you start a new thread. 2nd, the pressure should drop, the speed at which it drops is hard to describe but likely most would say a gradual drop and not instantly. Either way if you are getting @ least 55psi while cranking, I would expect it to start or at least try. From there I would check spark next.
98 Silverado k1500 4x4 350


 
someotherguy 
Moderator
Posts: 25679
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
04-06-11 03:33 PM - Post#2072825    
    In response to 355Cheyenne

TBI's bleed the pressure off pretty quickly; Vortecs aren't really supposed to but many do and still run fine. It may be that the ones I've seen do this are displaying regulator failure and just haven't gotten bad enough to be obvious yet.

Anyway as he said you want to note the fuel pressure very closely; Vortec small blocks are very picky about it and won't start if it's even a couple pounds low.

Richard
94 C2500LD / 94 C1500 / 06 300C SRT8 .. and an LS-swapped 97 Suburban
Check out my truck shop projects


 
88S10SPORT 
Forum Newbie
Posts: 10

Reg: 04-05-11
04-06-11 06:28 PM - Post#2072931    
    In response to someotherguy

I didn't want to make a thread quite yet until I figured that out so I had more info. Thanks for the replies definitely though, I might have a thread started about it soon. Thanks again!

 
rs64 
Forum Newbie
Posts: 18

Reg: 04-10-10
12-13-12 10:06 AM - Post#2297565    
    In response to someotherguy

jegs has cut that actroncp7817 to 14.99 mine was 19.98 total with shipping //// i still dont know should you test the pump and other line seprate or all at the same time if all the same how can you tell if its the pump or something else ??thanks robert


Edited by rs64 on 12-13-12 10:07 AM. Reason for edit: No reason given.

 
Chevytech 
Subject Matter Expert - Senior Member
Posts: 2998

Loc: Twin Cities, Minnesota, U...
Reg: 04-25-04
12-13-12 02:56 PM - Post#2297623    
    In response to rs64

  • rs64 Said:
...i still dont know should you test the pump and other line seprate or all at the same time if all the same how can you tell if its the pump or something else ??thanks robert



http://67-72chevytrucks.com/vboard/showpost.php?s=...
For those of you that are wondering why you are not getting replies to your thread:

Did you give the model, year, engine, fuel system type, and transmission information?

If the it has been altered from stock let us know about that too.


 
Suburbanite88 
Forum Newbie
Posts: 40

Age: 50
Loc: United States
Reg: 11-07-13
11-25-13 02:44 PM - Post#2402607    
    In response to someotherguy

Having major problems.
1988 V20 350/400 TBI in bad shape.
Seems Fuel Starved and/or Vacuum Leak, maybe that split hose thing, haven't dropped the tank yet, there's 25 gallons of gas in it, I live in a condo...
Gonna try the Fuel Pressure Test first.
Your Test Gauge recommendation for Harbor Freight is a good one, except the ad mentions NOT COMPATIBLE with GM TBI...

Just thought you'd like to know:

Fuel Injection Pump Tester
Check fuel pump pressure on most systems with this fuel injection pump tester.

Only: $29.99
Sale: $19.99

http://www.harborfreight.com/fuel-injection-pump-t ester-92699(dot)html

Name: Fuel Injection Pump Tester
SKU: 92699
Brand: Pittsburgh Automotive
Compatible with: Fits most systems (except For Bosch, Cis-jetronic And GM Throttle Body Systems)

 
someotherguy 
Moderator
Posts: 25679
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
11-25-13 09:31 PM - Post#2402708    
    In response to Suburbanite88

I'm aware that it says that; you may want to consider I've actually used the thing for the purpose I mention. My quote - "doesn't have a TBI adapter but can be T'd in with scrap hose as shown in last pic"

As far as a bunch of gas in the tank, that's what a siphon hose and a large gas can is for. Transfer to another vehicle or buy a couple extra cans. Any amount you remove from that tank will make dropping it all the easier.

Richard
94 C2500LD / 94 C1500 / 06 300C SRT8 .. and an LS-swapped 97 Suburban
Check out my truck shop projects


 
klaborde 
Forum Newbie
Posts: 9

Reg: 12-13-13
12-25-13 01:59 PM - Post#2410479    
    In response to Chevytech

on my 94 chevy, I've gone through 7 fuel pumps. and they all run bout 15 to 35 seconds before shutnoff. and im still having trouble. it'll crank and u go down the road and it'll die crank it up and when it starts, dies instant,try again it will start, but it turns over like its weak! not always though. and it smells the raw fuel by exhaust. ii've changed all the sensors, put a new tbi, and new distributor. also changed fuel filter. and last year put a new ecm!! im stumped!!!

 
Low priced Genuine GM Auto Parts
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