95 3.1 hard starting finally died
the6
11-20-2005, 05:43 PM
last year i did my twice yearly oil change. i put an acdelco filter ( always used fram)and vavoline 10w30 oil in it and changed the air filter. right after that it started being really hard to start. but it ran ok after it started. then it started jerking like you turned the key off and on. everyone said bad fuel pump. i replaced it still did the same thing. when you turned the key on no fuel pump came on i took off the gas line and had my wife try and start it after cranking it for 3 or 4 min. gas came out the tube. i broke down and bought a manual. the fuel pump is wired through the oil pressure sending unit. i installed a new sending unit still same problem. i changed the oil and filter this time with a fram. it took forever to get up oil pressure but whwn it did it started. now it wants to stall a lot but it runs when driving. i'm going to replace the oil pump with a high volume pump and see it it cures the problem. :banghead:
maxwedge
11-20-2005, 06:04 PM
Stop with the oil pump, you are way off base here. Get a fuel pressure gage on the fuel rail and look at fuel pressure key on only, then running, around 45-50 psi. Check the vacuum hose to the regulator for raw fuel , this would indicate a bad fuel press reg. How recent is the fuel filter this can cause what you describe also.
the6
11-20-2005, 06:16 PM
Stop with the oil pump, you are way off base here. Get a fuel pressure gage on the fuel rail and look at fuel pressure key on only, then running, around 45-50 psi. Check the vacuum hose to the regulator for raw fuel , this would indicate a bad fuel press reg. How recent is the fuel filter this can cause what you describe also.
it has a throtal body. it's not injected. i shorted the oil pressure sending unit with a paper clip it has 3 wires i shorted the 2 across from each other and turned the key on after reconnecting the fuel line, it started right up. beleive me i don't want to have to take down that pan. it's an apv with 160k on it.
it has a throtal body. it's not injected. i shorted the oil pressure sending unit with a paper clip it has 3 wires i shorted the 2 across from each other and turned the key on after reconnecting the fuel line, it started right up. beleive me i don't want to have to take down that pan. it's an apv with 160k on it.
maxwedge
11-20-2005, 07:05 PM
A 95 Lumina has port FI, not throttle body injection. This is not an oil pump problem period. Get a mechanical gage on the engine and check the oil pressure before doing anything that major.
the6
11-20-2005, 09:05 PM
A 95 Lumina has port FI, not throttle body injection. This is not an oil pump problem period. Get a mechanical gage on the engine and check the oil pressure before doing anything that major.
sorry max but it is a throttle body. not port FI. unless FI changed to gas spewing injectors over the throttle plates. But i am going to take your advise on putting a manual gauge on it and i'll let you know what it reads.
i'll give you another problem i had in my 91 3.8 1500 truck. it would quit when it reached 180. i tried to figure it out new ecm and stuff but had to have the truck for work so i took it to the shop.it took them 8 hours to figure it out it was the temp. sending unit. $6.00 cost for finding it $125 and no i didn't get any ky with the bill. now i can't find oit why the gauge quit 2 weeks ago. it goes clear over when you go to start but won't show temp. voltage at the sending unit (which i replaced is what the book says) and i changet the ecm no work. :banghead:
sorry max but it is a throttle body. not port FI. unless FI changed to gas spewing injectors over the throttle plates. But i am going to take your advise on putting a manual gauge on it and i'll let you know what it reads.
i'll give you another problem i had in my 91 3.8 1500 truck. it would quit when it reached 180. i tried to figure it out new ecm and stuff but had to have the truck for work so i took it to the shop.it took them 8 hours to figure it out it was the temp. sending unit. $6.00 cost for finding it $125 and no i didn't get any ky with the bill. now i can't find oit why the gauge quit 2 weeks ago. it goes clear over when you go to start but won't show temp. voltage at the sending unit (which i replaced is what the book says) and i changet the ecm no work. :banghead:
jeffcoslacker
11-21-2005, 05:32 AM
Make sure you don't have a problem with your wiring to the injectors by giving the harness a good tug and shake while it's running, if you can get it running.
Do you seem to have an oddly large amount of fuel spraying when you try to start it? I ask because I've seen coolant temp sensors go bad on the TBI motors and make the injectors flow so rich it drowns the motor.
You can see it when cranking, they are blowing like showerheads instead of a fine mist. Yoiu shouldn't really see the spray pattern, just the droplets rolling across the plate as they condense on it.
And smell like fuel real bad when they do it.
Just re-read your post, I missed the point altogether. I'm on major pain medication, kinda not with the program, sorry. Maybe there's something useful here...
Do you seem to have an oddly large amount of fuel spraying when you try to start it? I ask because I've seen coolant temp sensors go bad on the TBI motors and make the injectors flow so rich it drowns the motor.
You can see it when cranking, they are blowing like showerheads instead of a fine mist. Yoiu shouldn't really see the spray pattern, just the droplets rolling across the plate as they condense on it.
And smell like fuel real bad when they do it.
Just re-read your post, I missed the point altogether. I'm on major pain medication, kinda not with the program, sorry. Maybe there's something useful here...
jeffcoslacker
11-21-2005, 05:35 AM
I'd be tempted to go around the oil pressure fail-safe and just give the fuel pump a direct 12v fused feed off the ignition and see how it goes before I'd change an oil pump...
jeffcoslacker
11-21-2005, 05:39 AM
If the pressure fail safe really is the key to the problem, I'd wonder if the pump's intake screen got blocked a bit and now it's hard for it to generate nominal oil pressure when cranking to ground the fuel circuit.
I guess you'd have to get a gauge reading right off the sensor port and see....wait, that's what max said, huh? Smart dude :)
I guess you'd have to get a gauge reading right off the sensor port and see....wait, that's what max said, huh? Smart dude :)
jeffcoslacker
11-21-2005, 05:43 AM
Give that pigtail and wiring a shake down at the sender too while it idles, see if it breaks up and you just have a bad pigtail (common) before doing anything drastic.
It's awful suspicious that the trouble started right after an oil change. that's usually not coincidence.
It's awful suspicious that the trouble started right after an oil change. that's usually not coincidence.
the6
11-22-2005, 11:25 PM
well i got my snow shoes off. my wife took the van to the store it ran perfect till she pulled into the drive. and it died. about 100 feet from the garage. i let it set there i figure if i'm going to freeze my ass off it could too. iwent out and it started and ran fine for about 3 seconds so i pulled off the sending unit plug and shorted it and the damn thing started right up. i'm really begening to hate that van. i still havent found my gauge yet i will get one tomorrow. i agree about the oil change and the problem with starting started at the same time. i couldn't figure out what i did or moved just changing the oil and air filter. but as soon as it was done the hard starting began.
the6
11-23-2005, 07:14 PM
i got the word today if i touch the van befor turkey day is over and not help get ready for the family i will die from having my nuts cut off. guess i'll wait till friday. i kinda like having those litle pupies.
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