89 gmc 1 ton runs bad

prostock_50 · 09-29-2008, 10:29 AM

got a 89 gmc 1 ton 454 started running bad. did drive it about 400 miles before this started. have replaced the distributor,fuel pump relay,dual tank switching valve,tank switch,checked fuel pressure both tanks fuel pumps have around 11 psi. it will start and idle but driving it about 1/4 mile it will die.starts back up but still wont run. have timing set at 4 degree what it calls for. new gaskets on tbi. the reason i replaced the distributor was the truck been sitting while i was working on the body and durning the 400 miles that i did drive the truck it ran fine. but the distributor was was rusted on the inside and broke it trying to get the shaft out. so thats why i replaced it. now it gives me a code of 44 which is a lean exhaust condition. could the be the oxygen sensor. NEED SOME HELP.

Case 7230 · 09-29-2008, 11:06 AM

Check for a vacuum leak. Hopefully the new TBI gasket has eliminated any leaks there. Also check the Idle air control valve in case it is stuck. If you still think it may be the oxygen sensor go to the repair section of autozone.com for instructions on how to test it. I would also have a look at the EGR valve, it may need cleaned.Hope this helps.

leolkfrm · 09-29-2008, 05:44 PM

Good list of checks, I would start at the egr only because I've seen it on the 454, it may not be seating properly

prostock_50 · 10-01-2008, 09:42 PM

well still wont run got about 400 ft and started to die. sure glad its a 4 speed put in 2nd gear and crank it back home lol. everything you guys said to check checked out ok. iam thinking its the fuel pumps right side goes to 8 psi when key is turned on starts goes to 11 psi, left side nothing when key is turned on can hear pump running no fuel pressure. get it started on right side switch to left hear pump running engine starts to die and no fuel pressure and i just put the fuel tanks back on and the new bed o well live n learn i guess. lol

leolkfrm · 10-02-2008, 06:26 AM

I'm confused, back in in the late 80's gm went to 1 large in frame fuel tank. You have 2? If you have converted it you may need a pump between the engine and switch.

03chevy · 10-02-2008, 07:16 AM

when is the last time you bought a new gas cap? my bro's ex girlfriend has a vette and that was the problem. start everytime after you run 1/4 to a mile would just die and had to set a few mins. and do it all over again. until i bought a gas cap for it.

prostock_50 · 10-07-2008, 07:55 PM

it was a bad fuel pump right side tank, and the little rubber hose between the fuel pump and fuel pump outlet line the rubber was torn and soft had the fuel line in the tank stopped up. and yes it is a 89 1 ton has the old body style same as my 74 chevy 1 ton. the only thing different in the hood and front fenders.

leolkfrm · 10-09-2008, 07:21 AM

cool thanks for posting the results, ya never know who it will help down the road!

RoadHammerTLM · 10-09-2008, 08:10 AM

Really weird, we even had a 89' Chevy 1 ton extend cab and it had a 454 with only 1 in frame fuel tank. We had to install a bed mounted second tank for our long RV trips out west because it would not hold enough fuel.

Hammer

87c10slammer · 10-09-2008, 10:38 AM

my 87 has 2 tanks. one on each side. i think it was jsut an option with some of them. my truck is a silverado editon so that may make a difference.

09-29-2008, 10:29 AM	#1
prostock_50 Junior Member Join Date: Sep 2008 Posts: 3	89 gmc 1 ton runs bad got a 89 gmc 1 ton 454 started running bad. did drive it about 400 miles before this started. have replaced the distributor,fuel pump relay,dual tank switching valve,tank switch,checked fuel pressure both tanks fuel pumps have around 11 psi. it will start and idle but driving it about 1/4 mile it will die.starts back up but still wont run. have timing set at 4 degree what it calls for. new gaskets on tbi. the reason i replaced the distributor was the truck been sitting while i was working on the body and durning the 400 miles that i did drive the truck it ran fine. but the distributor was was rusted on the inside and broke it trying to get the shaft out. so thats why i replaced it. now it gives me a code of 44 which is a lean exhaust condition. could the be the oxygen sensor. NEED SOME HELP.

09-29-2008, 05:44 PM	#3
leolkfrm Senior Member Join Date: Mar 2008 Location: N.Y. Posts: 1,074	Good list of checks, I would start at the egr only because I've seen it on the 454, it may not be seating properly __________________ 4 wheels move the body 2 wheels move the soul

10-02-2008, 06:26 AM	#5
leolkfrm Senior Member Join Date: Mar 2008 Location: N.Y. Posts: 1,074	I'm confused, back in in the late 80's gm went to 1 large in frame fuel tank. You have 2? If you have converted it you may need a pump between the engine and switch. __________________ 4 wheels move the body 2 wheels move the soul

10-02-2008, 07:16 AM	#6
03chevy Senior Member Join Date: Dec 2006 Location: jax,fl Posts: 991	when is the last time you bought a new gas cap? my bro's ex girlfriend has a vette and that was the problem. start everytime after you run 1/4 to a mile would just die and had to set a few mins. and do it all over again. until i bought a gas cap for it. __________________ A dirty mind is a terrible thing to waste!

10-07-2008, 07:55 PM	#7
prostock_50 Junior Member Join Date: Sep 2008 Posts: 3	problem fixed it was a bad fuel pump right side tank, and the little rubber hose between the fuel pump and fuel pump outlet line the rubber was torn and soft had the fuel line in the tank stopped up. and yes it is a 89 1 ton has the old body style same as my 74 chevy 1 ton. the only thing different in the hood and front fenders.

09-29-2008, 11:06 AM	#2
Case 7230 Senior Member Join Date: Dec 2007 Posts: 231	Check for a vacuum leak. Hopefully the new TBI gasket has eliminated any leaks there. Also check the Idle air control valve in case it is stuck. If you still think it may be the oxygen sensor go to the repair section of autozone.com for instructions on how to test it. I would also have a look at the EGR valve, it may need cleaned.Hope this helps.

10-01-2008, 09:42 PM	#4
prostock_50 Junior Member Join Date: Sep 2008 Posts: 3	well still wont run got about 400 ft and started to die. sure glad its a 4 speed put in 2nd gear and crank it back home lol. everything you guys said to check checked out ok. iam thinking its the fuel pumps right side goes to 8 psi when key is turned on starts goes to 11 psi, left side nothing when key is turned on can hear pump running no fuel pressure. get it started on right side switch to left hear pump running engine starts to die and no fuel pressure and i just put the fuel tanks back on and the new bed o well live n learn i guess. lol

10-09-2008, 07:21 AM	#8
leolkfrm Senior Member Join Date: Mar 2008 Location: N.Y. Posts: 1,074	cool thanks for posting the results, ya never know who it will help down the road! __________________ 4 wheels move the body 2 wheels move the soul

10-09-2008, 08:10 AM	#9
RoadHammerTLM Senior Member Join Date: Sep 2008 Posts: 250	Really weird, we even had a 89' Chevy 1 ton extend cab and it had a 454 with only 1 in frame fuel tank. We had to install a bed mounted second tank for our long RV trips out west because it would not hold enough fuel. Hammer

10-09-2008, 10:38 AM	#10
87c10slammer Senior Member Join Date: Mar 2008 Location: levittown pa Posts: 2,174	my 87 has 2 tanks. one on each side. i think it was jsut an option with some of them. my truck is a silverado editon so that may make a difference.

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