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I am really hoping that someone can shed some light on this ongoing issue I’ve been having with my Sunfire. It’s a 1995 2.2L with like 129,000 miles. My problem is this…I was leaving my buddies late last night and when I started my car it took a few seconds of cranking, as it sometimes does, before it finally started up. Once started I could feel it was idling kind of sluggish. When I put it in reverse and pushed on the gas the car rumbles as if it wants to die but it still moved very slowly and sluggish. Made it to the street and put it in drive and it was doing the same thing. You push on the gas and it just wasn’t driving/pulling/catching/getting then power it should (however you want to word it) but it was just sluggishly moving. Then once it had been going for a sec it would catch all the sudden and you get the pull you should be with how hard you’re hitting the gas. Then it would start rumbling again. Then whenever you slowed down or stopped it would start all over again. Made it back to my buddies house and had my friend, who is above average in car knowledge, and let him drive it. It did the same thing. I wasn’t paying that much attention but he said it wasn’t going above like 3000 RPM. We just barely had the power to make it back up his driveway. We have concluded that it’s obviously something fuel or spark related. The car runs fine other than this issue. I have had this happen a few times before last night where I would push on the gas and not get the power that I should but in the past it would happen quickly and then stop. Never to the point that I couldn’t drive anywhere. I do often have to crank it for a few seconds when starting for it to finally come on. The check engine light has been coming on for a couple of months now. I’ve noticed it comes on most usually at night or on days when it’s wet and rainy. Brought it to get the error code read and apparently my fuse that controls the car lighter is blown and that also controls the error reader. I’m assuming it’s a 02 sensor or sensor of some kind. My buddy and I just not even two weeks ago did some basic maintenance on the car. We changed the air filter, fuel filter, oil + oil filter and spark plugs + wires. The car has run fine since then up until last night. When we were changing the spark plugs there was one (the one on the far right looking at the engine) that had oil on it. We thought maybe it was just from all the grimey stuff on/around the plugs on the engine heating up and leaking in.

Well that’s about all the info I can think to give guys. As I said, we’ve concluded it’s the spark plugs or maybe the fuel pump. Or something else fuel related. Don’t believe bad 02 sensors would cause this, would it? Or maybe a bad PVC valve? Any input would be greatly appreciated. My buddy and I are going to check the spark plugs after work today and go from there. Definitely going to try and find and replace that fuse so we can see why my check engine light is coming on.  

Alright I am back today with a small update. Due to the weather we weren’t really able to do a whole lot after work yesterday. I got to my friend’s house and we tried starting it just to see if sitting over night did anything. It didn’t. When we tried then the car wouldn’t crank up. Well, it would crank but just wouldn’t start. I just did my fuel filter a couple weeks ago and I know what my fuel pump sounds like and I didn’t think I was hearing it engage and neither did my buddy. So we started moving towards the fuel pump. Well we braked due to weather and went out to dinner. We planned to come back and do an actual check to see if the fuel pump was working but just for the hell of it we tried starting it again. It started this time! Though it was idling very rough though. Didn’t even try driving it anywhere as it was obvious it wasn’t going to make it. After about 10-15 min it stuttered and died on its own. Got it started again and tried revving it up. It revs to exactly 4K, backfires/misfires and then rumbles down to almost dying. Tried many times and it will not go over 4K and does the same thing every time you get it up that high. We were able to check the fuse that I was told was bad and it wasn’t. The fuse is fine and the 12v for the car lighter works fine. Found out you just have to push whatever into it harder than usual. So I don’t know why the error code reader wasn’t reading any codes to those people. We weren’t able to check the spark plugs for oil or do anything else really. We’re both kind of at a loss. He is thinking it might be something ECU related. I disagree. It seems very much like a fuel issue of some kind…

Any other help with this would be greatly appreciated!  

hi... my net is down.. i am at a friends...

can you hear the fuel pump turn on for 2 seconds when you turn the key on... this usually takes 2 people...

if you have a harbor freight tools store.. or a digital volt meter with a 15 amp DC or a 20 amp DC range... you can create a jumper with a fuse inline to look at the AMP draw of the fuel pump while in operation...

i don't know if the 95 takes the tiny fuses or the normal flat fuses for the fuel pump at the fuse box..

there are two different versions of these at harbor freight tools...



you locate the circuit to be tested.. remove the fuse... plug it in the side of the tool connector.. and plug the tool in..   you can now monitor the AMP draw of the fuel pumps...

these are 10 bucks each this week...

30 Amp Automotive Fuse Circuit Tester  Item #67724
or
20 Amp Automotive Fuse Circuit Tester Item #67725


on another forum.. there was a 95 that the owner did all kinds of stuff on.. spend months working on it... had failed to do this test even through he said he had....   when i quizzed him on it.. . he  ran the test...  started out a 7.1 amps... after 10 minutes it was up to 15 amps... when it got to 23 amps .. the engine died... and it set a cam sensor or a crank sensor code...  this was because the fuel pump was drawing so much power the crank and cam sensors did not have enough voltage to operate... so it set a code for them..


if you can find the fuel pump RELAY...  i would like you to get the car running..    reach over and UNPLUG the fuel pump relay...  this tests the OIL pressure switch fuel pump contacts inside...  when the engine is running .. the oil pressure switch sends most of the power to the fuel pump...

i have found the fuel pump relays burned and the sockets burned... where too much current was passing through the relay instead of just  a few seconds during start up...

you will also want to print this image below.... post the results to test 1, 2, 3, 4 by number..  so i can verify if you have good ground connections...

 

Hey bud, thanks very much for you advise. Unfortunately though this is the first time Ive checked this since posting it up. Sorry. I put stuff up on multiple forums trying to get to the bottom of this and this one didn't get put in my favorites to come check on.

But we still haven't made any progress with the car. I am at work and trying to do this quickly so I am going to copy and paste everything I can from my main forum I have been on. Anymore light you can shed after seeing everything would be greatly appreciated. I'd be happy to still do a pressure test or volt test if one of those could still be the issue.

Btw ,from the get go of my car having this issue I have not heard my fuel pump engaging. I know what it sounds like. Its a loud hum. When i replaced my fuel pump the week before the car breaking down I heard it engaging just fine when I primed the fuel after replacing the filter.

This is everything I have from the other forum I am on...

Alright I am back today with a small update. Due to the weather we weren’t really able to do a whole lot after work yesterday. I got to my friend’s house and we tried starting it just to see if sitting over night did anything. It didn’t. When we tried then the car wouldn’t crank up. Well, it would crank but just wouldn’t start. I just did my fuel filter a couple weeks ago and I know what my fuel pump sounds like and I didn’t think I was hearing it engage and neither did my buddy. So we started moving towards the fuel pump. Well we braked due to weather and went out to dinner. We planned to come back and do an actual check to see if the fuel pump was working but just for the hell of it we tried starting it again. It started this time! Though it was idling very rough though. Didn’t even try driving it anywhere as it was obvious it wasn’t going to make it. After about 10-15 min it stuttered and died on its own. Got it started again and tried revving it up. It revs to exactly 4K, backfires/misfires and then rumbles down to almost dying. Tried many times and it will not go over 4K and does the same thing every time you get it up that high. We were able to check the fuse that I was told was bad and it wasn’t. The fuse is fine and the 12v for the car lighter works fine. Found out you just have to push whatever into it harder than usual. So I don’t know why the error code reader wasn’t reading any codes to those people. We weren’t able to check the spark plugs for oil or do anything else really. We’re both kind of at a loss. He is thinking it might be something ECU related. I disagree. It seems very much like a fuel issue of some kind…

Alright I am finally back with another update. I still have not performed the pressure check as was suggested. Sorry, my buddy is kinda the one calling all the shots since he knows all about this stuff and he has said we don't need to do it. If I had a ride to get one and the know how to do it alone I'd be happy to try it. But here's what else we've done...

Bought a ODB2 code reader to check the codes but since the car wont start now its impossible to get the codes off it.

Bought and planned to install new coils but before we got started by buddies dad told us of a little trick to test the coils. So we took out one at a time all of the new plugs we put it, put them back into the wire, touched them to something grounded and tried starting the car. Every one sparked just fine, which as we were told, means the coils are working just fine.

Next we disconnected the fuel line from the fuel filter and attempted to start the car and nothing happened. Its my understanding that if the fuel pump was working at all then it would be trying to pump fuel when the car is being started and therefor should be leaking/spraying fuel from the line we disconnected. Went to get a new fuel pump and just for shits and giggles we brought my fuel relay switch to replace. When auto zone saw my relay switch they said it was in horrible condition and that it could very easily be the cause of my problems. It was rusted very badly and had what looked like heat bubbles or something on the top. We replaced that and it didn't help at all.

I have ordered a new fuel pump online (for $100 compared to $265 in store!) and it should be here this week I'm hoping.

I have never replaced a fuel pump but all I've ever heard is bad things about how difficult it is. My buddy seems really sure that we can get to it through the backseat so as not to have to drop the exhaust and all that jazz. I cant find anything definitive on that matter online. Some say no way its not possible and others say it is.

Any suggestions, advice or anything of any kind you can tell me?

I know it seems like I am not taking the advise being given but please understand that between the money I have available and the person I have helping me, it might not be the easiest thing for me to do some of the stuff asked.

I am just hoping that I didnt just waste $100 on this fuel pump and its something else.  

before you change the fuel pump.. and it can be BAD... its a serious failure..


the fuel pump has 2 sources of positive power...

a fuel pump relay
an oil pressure switches outer contacts..

this is what most GM fuel pump relays look like inside... you can easily in most cases use a pair of small screwdrivers and spread the sides of the cube to extract the insides..



i cleaned the contacts on this one..  but you can prove your fuel pump works by removing the cover.. and manually closing the contact plate down...   warning.. this one was worn enough that when you manually closed it down.. it would barely make contact.. when i closed it with the signal from the computer.. it would not close the contacts enough to run the pump...


this is what most GM oil pressure switches look like inside..

the center terminal is connected to the shell to control the gauge in the dash board...

the outer 2 contacts are closed when the oil pressure comes up...  this is where most of the current for the fuel pump comes from..   the skinny terminal relays do not really have the long term ability to run the pump properly..









when you turn the key to the ON position.. but before you have started to crank the engine..  the ECM/PCM turns on the fuel pump relay for 2 seconds.. this primes the fuel system.. as you start cranking.. the PCM turns on the fuel pump relay again and continues to keep it providing power for the fuel pump....

but..

there is the oil pressure switch in parallel...   when the engine first starts to crank..  there is not enough oil pressure to close the contacts shown above..  as soon as the engine starts.. the oil pressure comes up enough to close the contacts and  power the pump ...

if the oil pressure switch is bad.. the excess amperage through the relay will burn the terminals in the relay socket.. this reduces the easy flow of current and it gets hotter and hotter until it looses all contact..  or the relay melts..

this is also an issue for you 98 sunbird radiator cooling fan  relay..


~~~~~~~~~~~~~~~~~~~~~~~

i don't think you can access the fuel pump through the inside of the car.. this is done with japanese built models..   as it's required in japan... ease of repair..    the pontiac is going to have a solid floor pan.. so you are going to need to drop the tank...  not an easy job.. not impossible..

while you have it down...  you will also want to check the ground connection for the fuel pump... i don't know if its under the car.. or in the harness  and grounded to the buss bar grounds that are totally hidden usually in the rocker panels under the plastic trim where the door opens..


i wanted you to do the 4 part test to verify the GROUNDS are good at the front of the car...

if they are bad up front.. you can work on the back of the car for a month .. and its still not going to work until you get them fixed at the front of the car...

the harbor freight amp meter is going to save you..  as you can monitor the amp draw of the pump while its working.. .

like i said.. one guy bypassed that... spent months working on his car... only to find the fuel pump was the issue.. after 10 minutes.. it started to draw more amperage.. until the voltage on the supply circuit was so low.. the engine sensors shut off..