So here is the story, I bought some used oem fuel injectors online for my mitsubishi eclipse 1997 420a. The car was running fine before switching the injectors.

My mechanic replaced them for me, and when I drove the car home, everything was fine until I floored it.

The car started to die out when coasting to a stop. I could keep it from dying out by keeping my foot on the gas.

A lot of oil spilled out from the intake manifold oil recirculation to my cold air intake.
CEL gave a miss firing code. Turns out cylinder 4 wasn't firing at all.

He did a compression test and found out that the cylinder is losing compression.
It could be a possibility that the car had bad compression before hand, as I had alot of blow-by.

He told me the valves got damaged from the me driving with the bad injectors.

I said, cant I just replace the injector every thing will be fine?

he said no, the damage is already done. Even if i replaced the faulty injector the car will still run rough and will miss-fire

So its either a valve job or replace the injectors which my mechanic claims will do nothing.

what do you guys think of this?

so, if the car was running fine before the injectors were installed, then why did you replace the injectors. your mechanic is brainless btw

Originally posted by Venz
So here is the story, I bought some used oem fuel injectors online for my mitsubishi eclipse 1997 420a. The car was running fine before switching the injectors.

Why replace them then?

Originally posted by VenzMy mechanic replaced them for me, and when I drove the car home, everything was fine until I floored it. The car started to die out when coasting to a stop. I could keep it from dying out by keeping my foot on the gas. A lot of oil spilled out from the intake manifold oil recirculation to my cold air intake. CEL gave a miss firing code. Turns out cylinder 4 wasn't firing at all. He did a compression test and found out that the cylinder is losing compression. It could be a possibility that the car had bad compression before hand, as I had alot of blow-by. He told me the valves got damaged

Possibility. Did he do a leak down? I would wonder in that situation whether or not the piston/rings were any good. Could have been having a problem with worn rings prior and a stuck injector just exacerbated the problem (or a "testing" of the new injector install - high reving to be sure that the injector is working properly - may have been the "last straw").

Originally posted by Venz He told me the valves got damaged from the me driving with the bad injectors.

No I don't think so. Unless the injector caused excessive heat to be generated inside that cylinder (maybe lean?), I can't see it causing the valve to burn. Kinda a moot point now.

Originally posted by VenzI said, cant I just replace the injector every thing will be fine? he said no, the damage is already done. Even if i replaced the faulty injector the car will still run rough and will miss-fire

That is correct.

Replaced the injectors because my car was turbo'ed and i had higher flow injectors in them.

Originally posted by bullettdsm
No I don't think so. Unless the injector caused excessive heat to be generated inside that cylinder (maybe lean?), I can't see it causing the valve to burn. Kinda a moot point now.

isnt that basically my situation? one of the injectors wasnt working. thus, making the cylinder run super lean, causing damage.

Originally posted by bullettdsm

Originally posted by VenzI said, cant I just replace the injector every thing will be fine? he said no, the damage is already done. Even if i replaced the faulty injector the car will still run rough and will miss-fire

That is correct.

so you are saying there is no point for me to install a brand new injector in there because the cylinder will still run rough and misfire?

What exactly are your compression numbers?

Originally posted by Venz
so you are saying there is no point for me to install a brand new injector in there because the cylinder will still run rough and misfire?

IF you have a burnt valve, changing an injector will not fix the valve.

it is 80 psi compression

I understand it won't make the valves better, but the problem is I don't see how driving with bad injectors damaged my valves so bad that it needs a valve job.

And let's just say the cylinder has low compression, wouldn't the cylinder still work if I replaced the bad injectors so it can fire properly?

Originally posted by Venz
Replaced the injectors because my car was turbo'ed and i had higher flow injectors in them.

How much bigger did you go? I saw in your list on that site you posted says your tunning with a SAFC.

EDIT: Nevermind this post read it wrong. Sorry

Originally posted by bagged420a

Originally posted by Venz Replaced the injectors because my car was turbo'ed and i had higher flow injectors in them.

How much bigger did you go? I saw in your list on that site you posted says your tunning with a SAFC.

I think 270cc

drop about a half cap full of oil in that cylinder, then do another compression test. If it jumps, it's your rings/ring lands. If it doesnt, it's in your head.

Regardless of what happens, im sorry, but plan for a tear down. 80 is way low.