1991 3.1 mpfi cavalier rs wont start no engine light

billsbigf8 · 05-30-2009, 05:11 PM

driving my cav accelarated and car died out like a switch was flipped. i managed to get it to start when i got it towed home as soon as i hit throttle it died. no engine light. getting spark checked ok. when you give it a shot of starting fluid cranks over then dies. put a fuel guage on there getting 41psi when cranking and might start but most of the time not.and if i did get it start and idle it would do that for like 10 minutes and stall and then not start anymore for like a day. i did noticed that when i tried to give throttle when i had it running the psi would drop sometimes and then sometimes not .the psi when it was running at idle was 38 to 40 psi sometimes bouncing but most of the time staying steady. all the fuel pump functions work such as delay and and staying on whenit should. it is getting correct voltage. i also pushed the bleeder vauve on the psi guage when it was running did not stall it out. the last time i got it running today when i gave it throttle the psi dropped to like 30 and bounced back up to 38. this is the first time i noticed a psi drop. can a fuel pump get psi and not enough volume with still have psi at normal level? im pretty sure the injectors are fine b/c when its running idle its smooth not really rough.i know the coil packs are good tested them out ,new wires plugs,no vacum loss at all checkek all hoses wires, emish coponents. i really think its a fuel delivery problem. could this fuel pump be playing tricks on me. before it did this i took it for inspection and faild emishions high co2. i thought it was b/c it sat for 2 yrs in feild. put new gas in it high test so its not bad gas either. im going crazy tring to figure this out.please help.
bill

**mack1** · 05-30-2009, 05:24 PM

Hi Bill and welcome to TSF,

My guess would be restricted fuel flow. Likely the filter. I looked to see what the PSI is susposed to be, but I don't have a book that far back. A drop of 8 psi on accelerating is more than I would expect. I'm thinking that 4 to 6 psi drop is normal.

Not much help, but that is my thoughts.

Very best regards,
Mack1

**octaneman** · 05-30-2009, 08:26 PM

Hi billsbigf8

Disconnect the fuel regulator and see if the pressure drops. If it does drop then the pump is going bad or you got an air pocket somewhere in the gas line. If it doesn't drop then the regulator is bad.

Good luck !

**octaneman** · 05-30-2009, 08:31 PM

Hi billsbigf8

Disconnect the fuel regulator and see if the pressure drops. If it does drop then the pump is going bad or you got an air pocket somewhere in the gas line. If it doesn't drop then the regulator is bad.

Good luck !

05-30-2009, 05:11 PM	#1 (permalink)
billsbigf8 Registered User Join Date: May 2009 Posts: 1 OS: win xp	1991 3.1 mpfi cavalier rs wont start no engine light driving my cav accelarated and car died out like a switch was flipped. i managed to get it to start when i got it towed home as soon as i hit throttle it died. no engine light. getting spark checked ok. when you give it a shot of starting fluid cranks over then dies. put a fuel guage on there getting 41psi when cranking and might start but most of the time not.and if i did get it start and idle it would do that for like 10 minutes and stall and then not start anymore for like a day. i did noticed that when i tried to give throttle when i had it running the psi would drop sometimes and then sometimes not .the psi when it was running at idle was 38 to 40 psi sometimes bouncing but most of the time staying steady. all the fuel pump functions work such as delay and and staying on whenit should. it is getting correct voltage. i also pushed the bleeder vauve on the psi guage when it was running did not stall it out. the last time i got it running today when i gave it throttle the psi dropped to like 30 and bounced back up to 38. this is the first time i noticed a psi drop. can a fuel pump get psi and not enough volume with still have psi at normal level? im pretty sure the injectors are fine b/c when its running idle its smooth not really rough.i know the coil packs are good tested them out ,new wires plugs,no vacum loss at all checkek all hoses wires, emish coponents. i really think its a fuel delivery problem. could this fuel pump be playing tricks on me. before it did this i took it for inspection and faild emishions high co2. i thought it was b/c it sat for 2 yrs in feild. put new gas in it high test so its not bad gas either. im going crazy tring to figure this out.please help. bill

05-30-2009, 05:24 PM	#2 (permalink)
mack1 TSF Articles Team Join Date: Nov 2007 Location: Texarkana, Texas Posts: 1,245 OS: xp sp3 My System	Re: 1991 3.1 mpfi cavalier rs wont start no engine light Hi Bill and welcome to TSF, My guess would be restricted fuel flow. Likely the filter. I looked to see what the PSI is susposed to be, but I don't have a book that far back. A drop of 8 psi on accelerating is more than I would expect. I'm thinking that 4 to 6 psi drop is normal. Not much help, but that is my thoughts. Very best regards, Mack1 __________________ "If you like yourself others will like you also" me "Don't drink downstream from the herd" Will Rogers Submit New Articles Here

05-30-2009, 08:26 PM	#3 (permalink)
octaneman Mentor Home Support, Gearhead Automotive Center Join Date: May 2009 Posts: 541 OS: WINXP	Re: 1991 3.1 mpfi cavalier rs wont start no engine light Hi billsbigf8 Disconnect the fuel regulator and see if the pressure drops. If it does drop then the pump is going bad or you got an air pocket somewhere in the gas line. If it doesn't drop then the regulator is bad. Good luck !

05-30-2009, 08:31 PM	#4 (permalink)
octaneman Mentor Home Support, Gearhead Automotive Center Join Date: May 2009 Posts: 541 OS: WINXP	Re: 1991 3.1 mpfi cavalier rs wont start no engine light Hi billsbigf8 Disconnect the fuel regulator and see if the pressure drops. If it does drop then the pump is going bad or you got an air pocket somewhere in the gas line. If it doesn't drop then the regulator is bad. Good luck !