Engine problem
 

First I'd like to thanks anybody that will not complain about my english :rolleyes2:


I had some troubles with my Alero when starting it. The guys at the garage told me I had to clean my injector. I asked a friend of mine who is a mech and she told me that I could try the fuel injector cleaner before as it was only like 10$. So I believe the whole thing started there, when I used a STP fuel Injector Cleaner (the regular one). My engine was getting better, less chokes and everything but then my engine started to shake and smell like a lawnmower. We took the car, drove it in the highway and suddenly it got back to the nice, smoking-free car I had before ! We first tough that it was only junk that have taken off and that was blocking my cylinder ( so I was using like 5 or 4 cylinder instead of 6) or whatever it was. Seems like there's not enough intake and too much gas?

But no.

It came back and now it is worst. I can't start my car, when I finally manage to do it, it smells gas alot, I can't put my car on D because it chokes (the idle is rude) and gas is even dripping from my exhaust. I can't tell you how my car smokes too.

Help?
:(

Oh and I just changed my spark plugs, things are getting better, the only problem is the start and the idle. There's no problem when I accelerate.

Any "check engine" codes or lights on?

Obviously the car is running too rich, meaning there is too much fuel being fed to the engine.
This could be because of an intake leak, which lets in more air than usual, so the oxygen sensor sees more air than usual, and thinks the car is running lean, so the computers tell the injectors to add fuel. (This is a relatively common problem)

An intake leak would also explain the rough idle.

If you keep driving the car this way, you will kill the catalytic converter because of all the unburned fuel in the exhaust.

Do you see anything unusual when you do an inspection of the engine compartment?

injector cleaner dislodged junk, clogging causing an injector/s poppet to stick open, pouring gas into the combustion chamber.

That's my best guess.

could it almost be that your having a misfire type thing going on in the cylinders. it sounds like one or two cylinders are not getting a spark and so that its just pumping pure gas out of the exhaust, and thats why it wont start, and has a very rough idle, and is smoking, and smells bad.

Nope, nothing.
There's no light at all.

Also, my car ''drink'' gas more than before. I'm starting to believe the theory of a dislodged junk in my injector

The crappy running, the fuel dumping out the tail pipe, and increased consumption are likely caused by one or more stuck injectors (stuck open). I'd get them tested and/or replaced, but that's up to you.

I don't really see another option.
Is a clean-up, a real one, can fix this up or I have to change the whole thing?

Why don't you look into seeing how much a shop charges to recondition, or if they can backflush them.

Yeah i'll check this :D

I should change them all too?
Thanks

How much roughly do the injectors cost to buy brand new for the 3400 engine?

Not sure on that, but they are known to be a bad injector design, at least the early ones.
It would be a good idea to current-ramp all of them to make sure no other ones are going bad.

This happened to me when I had a set of aftermarket Coils installed on mine. I have the 2.4 and i have no clue if that is something you want to look into, but just wanted to drop it in. I had a loss of power, tons of fuel consumption and at times it wouldnt even start. When ever it did start raw fuel was being dumped through the exhaust.

I changed 2 coils out of 3, and my engine is better but still kind of drowning after a certain time.
The Idle is still rough, but when I press the gaz pedal, the engine is running really smooth.

I have 3 other coils too, with the whole system (the printed one? don't know if I can say this in english :p )


What do you mean?
I'm not a really good mech so could you explain a lil' more? :)

Well I can get mine for +- 59$ at my autopart. I'm just not sure how to detect an injector that is blocked.
Some one also told me that when an injector is blocked, it's usually being stuck closed and not because it is stuck open...

And I have a '99, so it might be what Comanche said...

new injectors on the 3.4... are approx $120 a piece! (i had to do o-rings on mine, and one injector was bad)

crazy expensive. I'd see if they can fix the ones you have.

Yeah, I have prices :rolleyes2:

I think I should start by the base, a compression test.

I also checked the sparks of my spark plugs, everything's fine but the sparkplug still smells gaz. I have 2 of them who're doing that.
No check engine light yet.

kazumaki, i'm pretty sure what he ment when he said to "current-ramp" is to upgrade the stuff with newer technology and design than having the old out dated stuff so it'll help you in a long run

no no no no.

Current ramp means to hook up an amp clamp around the injector power wire. Then run the car and look at the pattern that is created using an oscilloscope... expensive tools but VERY useful.

If oyu have the tools, the pattern should ramp up at a 45* angle(ish) and peak around 1amp. Around the middle there should be a little blip where the pintle overcomes the spring and pops up. It should be approx 3m/s long, IIRC.

Another great way to check is using a drop test. Get a pressure gauge and put it on the fuel rail. Run the car, note pressure. Use an injector pulse-er (another piece of test enquipment that you plug into the injector that turns it on/off) to pulse each injector 50 times. Not the psi drop in fuel pressure of each injector. Make sure to start/ run the car briefly between each injector as well. The psi readings should be within 1-3 psi. The lower the psi, the less fuel the injector delivered, and the more gummed up it is.

You may find, as well, that you lose fuel pressure when it's just sitting, and I'm assuming that it very may well do that, because the injectors will be leaking fuel. That's also why it's hard to start.. flooding it out. If you want to abosolutely 1000% diagnose them as leaking injectors, pinch off the feed and return lines to the rail and watch the pressure drop. If it bleeds down after pinching both of those lines it's the injectors leaking.

You'd probably have the best luck at a junk yard.. .find a smashed car with low mileage with a 3400 and pull the entire rail... they'll prolly give it to ya for $50.

Yeah I had a chance to get a Montana V6 3400 engine but it seems the injectors doesn't fit at all (both are LA1 engines). The Montana's one are rectangular and mines are circle shaped...

oops lol i tried ;)