need help bad - Pirate4x4.Com : 4x4 and Off-Road Forum

bignatedawg · 05-16-2005, 03:53 PM

I got a 1990 chevy 1500 ext cab short bed with a 350 it has that crapy throttle body injection on it. The problem is it will run for about 20-30 seconds and then it acts like its chokin itself out and sometimes i can play with the gas ennough to keep it runnin otherwise it just dies. I have had all my sensors checked such as the map and throttle postion and there both good i'm sure the o2 sensor is bad but i would think the truck would still run. I really have no idea what is wrong with it if u have ne info on how to fix it or ne thing let me know cuz I'm at my wits end with the thing and i really dont want to sell it but it gettin close to that point cuz i need a vehicle. So if u know ne thing i would greatly appreciate some help thanks. My email is bignatedawg3248@yahoo.com

s10bogger · 05-16-2005, 04:15 PM

What is your fuel pressure like? could be something in the fuel system (bad fuel pump or even just the fuel filter might have gotten blocked up). I had an old s10 do something along these lines a few years back. It ended up being a cross between the fuel pump and a worn out throttle body (the butterfly was loose do to a worn out bushing). It could also be an ignition problem (but if this was the case the truck would not want to start after).
I've also seen a clogged EGR valve cause another s10 of mine to run like shit (stalling out), I just took it off of the truck cleaned it out and put it back on...the truck did run better but I had to repeat this every 1500 miles or so (was a beater so I didn't want to sink a lot of money in it).
There is no way that an O2 sensor (no matter how fawked up) should make your motor die.
When the truck stalls out does it start right back up again or does it have issues and not want to start?? This will help in ruling out a few things.

orangefj45 · 05-16-2005, 05:13 PM

what's crappy about a tbi?

lumpdog · 05-16-2005, 05:27 PM

No kidding, TBI's rock, simple, low pressure, reliable, very few problems or expensive parts to leave you stranded.

Sounds like you have got a fuel issue.....check the pressures.

Next check you coolant temp sensor and map sensor. But it really sounds like to got some fuel issues......

bignatedawg · 05-16-2005, 05:36 PM

sometimes it will start rite back up but now it wont start at all since the last time i messed with it

s10bogger · 05-16-2005, 06:14 PM

When you turn the key (to the "on" position) but do not start the motor, can you hear the fuel pump prime the system? (It should run for a few seconds).
Check that and the fuel filter...I'm thinking more and more that it's your issue.

reddman · 05-16-2005, 07:17 PM

my buddies rig did the exact same thing when he put in a 327 with an aggressive cam. the map sensor wasnt giving the ecm a signal it knew what to do with (too little vacuum). i would check the map sensor. and while u are at it, change the coolant temp sens too. its less than 10 bucks and cures all kinds of ales.

05-16-2005, 03:53 PM	#1 (permalink)
bignatedawg Registered User Join Date: May 2005 Member # 47628 Location: oklahoma city Posts: 15	need help bad I got a 1990 chevy 1500 ext cab short bed with a 350 it has that crapy throttle body injection on it. The problem is it will run for about 20-30 seconds and then it acts like its chokin itself out and sometimes i can play with the gas ennough to keep it runnin otherwise it just dies. I have had all my sensors checked such as the map and throttle postion and there both good i'm sure the o2 sensor is bad but i would think the truck would still run. I really have no idea what is wrong with it if u have ne info on how to fix it or ne thing let me know cuz I'm at my wits end with the thing and i really dont want to sell it but it gettin close to that point cuz i need a vehicle. So if u know ne thing i would greatly appreciate some help thanks. My email is bignatedawg3248@yahoo.com Last edited by bignatedawg; 05-16-2005 at 03:56 PM.

05-16-2005, 04:15 PM	#2 (permalink)
s10bogger Registered User Join Date: Nov 2003 Member # 24405 Location: Stuck @ work Posts: 484	What is your fuel pressure like? could be something in the fuel system (bad fuel pump or even just the fuel filter might have gotten blocked up). I had an old s10 do something along these lines a few years back. It ended up being a cross between the fuel pump and a worn out throttle body (the butterfly was loose do to a worn out bushing). It could also be an ignition problem (but if this was the case the truck would not want to start after). I've also seen a clogged EGR valve cause another s10 of mine to run like shit (stalling out), I just took it off of the truck cleaned it out and put it back on...the truck did run better but I had to repeat this every 1500 miles or so (was a beater so I didn't want to sink a lot of money in it). There is no way that an O2 sensor (no matter how fawked up) should make your motor die. When the truck stalls out does it start right back up again or does it have issues and not want to start?? This will help in ruling out a few things. __________________ _____________________________________________

05-16-2005, 05:13 PM	#3 (permalink)
orangefj45 Registered User Join Date: Aug 2001 Member # 6816 Location: Fawk if I know Posts: 15,276	what's crappy about a tbi? __________________ Maybe you outta stick to legos!

05-16-2005, 06:14 PM	#6 (permalink)
s10bogger Registered User Join Date: Nov 2003 Member # 24405 Location: Stuck @ work Posts: 484	When you turn the key (to the "on" position) but do not start the motor, can you hear the fuel pump prime the system? (It should run for a few seconds). Check that and the fuel filter...I'm thinking more and more that it's your issue. __________________ _____________________________________________

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05-16-2005, 05:27 PM	#4 (permalink)
lumpdog Rock God Join Date: Mar 2005 Member # 44659 Location: Mtn Home, Idaho Posts: 1,237	No kidding, TBI's rock, simple, low pressure, reliable, very few problems or expensive parts to leave you stranded. Sounds like you have got a fuel issue.....check the pressures. Next check you coolant temp sensor and map sensor. But it really sounds like to got some fuel issues......

05-16-2005, 05:36 PM	#5 (permalink)
bignatedawg Registered User Join Date: May 2005 Member # 47628 Location: oklahoma city Posts: 15	sometimes it will start rite back up but now it wont start at all since the last time i messed with it

05-16-2005, 07:17 PM	#7 (permalink)
reddman Registered User Join Date: Dec 2004 Member # 39492 Location: SL,UT Posts: 2,334	my buddies rig did the exact same thing when he put in a 327 with an aggressive cam. the map sensor wasnt giving the ecm a signal it knew what to do with (too little vacuum). i would check the map sensor. and while u are at it, change the coolant temp sens too. its less than 10 bucks and cures all kinds of ales.