95 cpi hard start & breaks up under load
#1
95 cpi hard start & breaks up under load
Help. My 95 is hard to start sometimes, have to spray choke cleaner for it to start but the biggest problem is it breaks up under load & the longer you drive the less power it has, finally stalls & wont start.Wont go over 30 wnen it act up.
Parts replaced have been, fuel pump, filter, crank sensor, coil, plugs.
Could the cpi injector be bad?
It has no fuel smell when running & pressure is ok.
It could idle all day but when driven it acts up, acts like its starving for fuel
Parts replaced have been, fuel pump, filter, crank sensor, coil, plugs.
Could the cpi injector be bad?
It has no fuel smell when running & pressure is ok.
It could idle all day but when driven it acts up, acts like its starving for fuel
#2
RE: 95 cpi hard start & breaks up under load
Is SES light on? If so, get the codes read first to narrow down.
Yes, it could be the cpi unit, but specifically thefuel pressure regulator. It sounds to me like this might be your problem. I wrote a very detailed DIY article on this - search for fuel pressure regulator.
Also, if you do pop off the plenum to check, you can pressurize the system by leaving the key in the "on" position, but with the neg battery terminal disconnected, then touch it to the battery while checking out the cpi unit and fuel lines for leaks. If you are around 110k miles and the fuel efficiency has been dropping, I would venture to guess this is what the prob is because these go out reliably around this milage. ~$45 to replace.
If this is the prob, hopefully your cat hasn't died yet, but if it's clunking you'll need to replace it too. Also check and clean both O2 sensorsor replace them. I had to replace both on 2 95's I have that had this problem as well as the cats and a muffleralso on one. Crappy.
Yes, it could be the cpi unit, but specifically thefuel pressure regulator. It sounds to me like this might be your problem. I wrote a very detailed DIY article on this - search for fuel pressure regulator.
Also, if you do pop off the plenum to check, you can pressurize the system by leaving the key in the "on" position, but with the neg battery terminal disconnected, then touch it to the battery while checking out the cpi unit and fuel lines for leaks. If you are around 110k miles and the fuel efficiency has been dropping, I would venture to guess this is what the prob is because these go out reliably around this milage. ~$45 to replace.
If this is the prob, hopefully your cat hasn't died yet, but if it's clunking you'll need to replace it too. Also check and clean both O2 sensorsor replace them. I had to replace both on 2 95's I have that had this problem as well as the cats and a muffleralso on one. Crappy.
#3
RE: 95 cpi hard start & breaks up under load
Yes the SES light is on but I cannot get it to flash & cannot establish comm with scanners so there must be a wiring prob there too, I havent smelled any fuel but i will take plennum off & see.
I would like to solve the SES light mistery, its one thing after another with this year
I would like to solve the SES light mistery, its one thing after another with this year
#4
RE: 95 cpi hard start & breaks up under load
Ya, that's going to be tough without the codes. Could be a failing computer. There are some recalls on the abs controlin the computerthat you could call on the dealership to try to fix, and if they can't maybe they'd be willing to throw in some help with the ECU.
The FPR failure on these is so regular that you can almost bet on it. It won't really start smelling like fuel until it gets really bad because the cat and exhaust recirculation will take care of quite a bit of it until things just start failing/becoming overwhelmed.Even if it isn't the problem now - it probably will be later [&:]. haha.
GMreally should take the initiative on these types of recurring problems and offer some kind of recompense to owners, just like toyota does [:@]. I do however love the vehicle, so it's tough and of course these 95's are the bastard year.
The FPR failure on these is so regular that you can almost bet on it. It won't really start smelling like fuel until it gets really bad because the cat and exhaust recirculation will take care of quite a bit of it until things just start failing/becoming overwhelmed.Even if it isn't the problem now - it probably will be later [&:]. haha.
GMreally should take the initiative on these types of recurring problems and offer some kind of recompense to owners, just like toyota does [:@]. I do however love the vehicle, so it's tough and of course these 95's are the bastard year.
#5
RE: 95 cpi hard start & breaks up under load
I was able to order the regulator ($31) & the injector ($71) from advance online only, it will take longer to reach me but they were cheap enough. The regulator had "clean" signs of leaking & Im doing the injector for good measure since Im in there.
The SES is still a mistery, I tried grounding the data(ppl) wire AT the vcm & light still not flashed. Parts are so expensive for this year you cant even speculate & replace parts that may need changing soon
The SES is still a mistery, I tried grounding the data(ppl) wire AT the vcm & light still not flashed. Parts are so expensive for this year you cant even speculate & replace parts that may need changing soon
#6
RE: 95 cpi hard start & breaks up under load
Yeah, advance used to sell the regulator in-store for 31, but then stopped and upped the price to like 40 or 50. Good that you can still get it online for cheap, but actually they are technically diff companies.
I'm not sure what you mean about other things being so expensive though. I've found most things are either bleedover from Gen1 blazers, or just the same as the rest of the Gen2's. I call it the bastard year because it's neither one or the other, but generally the stuff I've had to get didn't seem out of the ordinarycost for blazers. I used to drive an acura legend, and let me tell you - that sob's partswere $$$$$.
If you found washing, you've def caught the problem. Just make sure to pressurize the system like I said to see if there's anything else under there leaking out.
I'm not sure what you mean about other things being so expensive though. I've found most things are either bleedover from Gen1 blazers, or just the same as the rest of the Gen2's. I call it the bastard year because it's neither one or the other, but generally the stuff I've had to get didn't seem out of the ordinarycost for blazers. I used to drive an acura legend, and let me tell you - that sob's partswere $$$$$.
If you found washing, you've def caught the problem. Just make sure to pressurize the system like I said to see if there's anything else under there leaking out.
#7
RE: 95 cpi hard start & breaks up under load
I just got an e-mail that the injector is not available, I really wanted to replace it while I was in there but I refuse to pay $300 for it. The regulator will be here next week & hopefully I can be trouble free for at least a while.
I did pressurize the system & had no leaks while pressurized, possibly leaking regulator while running then.
The expensive parts I mentioned were the differences in this year, cap, rotor, injection sys, O2 sensors compared with TBI models
I did pressurize the system & had no leaks while pressurized, possibly leaking regulator while running then.
The expensive parts I mentioned were the differences in this year, cap, rotor, injection sys, O2 sensors compared with TBI models
#8
RE: 95 cpi hard start & breaks up under load
Yeah, the injector assembly rarely fails, so I don't think you'll be having a problem with that. Even if it does, it's a good one to get from a junk yard. If the new regulator doesn't fix the problem, you might have a small leak in the fuel lines running to the central injector assembly.
One of the regulatorsI replaced was only slowly dribbling fuel out the open end, even though the truck was running very rough.
Yeah, the cap and rotor diff is a bit of a pain. I founda really cheap set over at Pepboys (I think) though, butdidn't know the O2's are diff.
One of the regulatorsI replaced was only slowly dribbling fuel out the open end, even though the truck was running very rough.
Yeah, the cap and rotor diff is a bit of a pain. I founda really cheap set over at Pepboys (I think) though, butdidn't know the O2's are diff.
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