2000 Grand Prix - Bad Fuel Injectors

[felx29]

I've been having a problem with the car for quite some time now. The
car has 150,000 miles on it, and since I bought it has had power and
hesitation problems with the engine. Basically it will stall and
sputter if you turn the wheel too far backing out of a space, or if
sitting idle, when hitting the gas it will take 2-3 seconds and buck to
get going. This doesn't happen all the time, but often enough where
it's annoying. Most recently the car will sputter without turning the wheel but while sitting idle.
Several times a "rich fuel mixture" has come back from the check engine
light, but this comes and goes. The oxegen sensors have been replaced, as have the plugs and wires, very recently. Is the last possibility the
fuel injectors ? I've heard that they can be a problem with cars like
this, and if they are, are they worth replacing them at this point? It
doesn't really hurt the car overall except for with the mileage, just more of a nuisance at this point. It might be too cost prohibitive however.

Any help would be appreciated !!

[BNaylor]

Welcome to AF.

Helpful to list your engine size and GP model so others can help out.

[felx29]

Yes I suppose that would help too.

It's a Grand Prix SE Sedan, I believe it's got the smallest engine available, which makes it a 1.8 liter.

Thanks!

[maxwedge]

Originally Posted by felx29

Yes I suppose that would help too.

It's a Grand Prix SE Sedan, I believe it's got the smallest engine available, which makes it a 1.8 liter.

Thanks!

There is no 1.8 in a Grand Prix, look under the hood on the engine top close out cover or intake manifold.

[felx29]

It's a 3100 SFI, 3.1 Liter according to the sticker.

Hope that helps, because obviously I don't have a good idea!!

Thanks.

[BNaylor]

Originally Posted by maxwedge

There is no 1.8 in a Grand Prix, look under the hood on the engine top close out cover or intake manifold.

He probably meant to say 189 cid which is 3.1L V6 Vin J.

PITA to prove it is the fuel injectors short of replacing them. Hard to test with NOID or any test light. The 3.1L that is.

[felx29]

Would it be big money to have to replace the fuel injectors, or at this point is it worth it? Other than this problem, the car is in good shape and the engine runs well, never had any major problems with it.

[BNaylor]

Originally Posted by felx29

Would it be big money to have to replace the fuel injectors, or at this point is it worth it? Other than this problem, the car is in good shape and the engine runs well, never had any major problems with it.

Before you do that is the problem only at idle or does it run bad in other rpm ranges?

[felx29]

It seems to run great once it gets going, it's very smooth, and there's not a lot of hesitation. Sometimes it takes some time/effort to get up to 70-75, but it's not a big engine to begin with. Basically if you're sitting at a stop light, you hit the gas, it hesitates, then finally kicks in and goes.

Not sure if this is related, but recently the engine seems to be running hotter than normal, but that also has come and gone and just started recently. The thermostat has been replaced in the past year plus as well.

One more random thing, recently I've also seen the idle jump up and down, sometimes when it's sitting idle. Weird, but not sure if it's related.

[BNaylor]

Just to make sure and it won't cost that much you might clean the throttle body with carb or throttle body spray cleaner and clean the idle air controller (IAT) and the seat on the throttle body. No not move the spring loaded pintle on the IAC but spray with cleaner only.

With your mileage it is possible you could have one or more flaky fuel injectors. Sometimes getting them professionally cleaned works and is cheaper than outright replacement.