Advice: 3.2 Popping on Acceleration

[crashr]

Hi Guys,

I am just finishing up my 2.7 to 3.2 engine coversion. I took the car around the block yesterday and notice that on acceleration there is popping coming from the exhaust. The car also takes a few moments to idle smoothly when first starting up.

I have done some searches on this and the only results I could find were in relation to 2.7L and 3.0L engines and I was wondering with the 3.2L if that would rule some of the standard suggestions out. What I have seen as possible causes are:

1) pulled head studs (I hope not, cuz I just bought this engine from speedster 94; also I din't think this was as much a problem with the 3.2's)
2) vacuum leak
3) spark plug gap
4) timing

Can anyone make any suggestions as to what they think it might be and how I should go about checking out the problem?

Thanks,

[Esel Mann]

crashr,

For what it's worth, I had the same problem. odd idle on start-up and an ocassional popping.

My mechanic determined that the heat isolation spacers and gaskets between the intake and cylinder head were shot on a couple of the cylinders. Thus the cylinder would pull in more air through the leak.
The popping was more noticable at lower rpms than at higher rpms.

He replaced the heat isolation spacers and gaskets and voila!!! Both issues disappeared.

For additional information, my 3.2 is in a 1984 Carrera, thus one can expect (and I am finding) that with an engine that is around 22 years old, things like hoses, gaskets, non-metallic spacers, and seals are well simply old and wearing out.

Regards,
Carlton

[bell]

if you're getting popping under acceleration then it sounds like it's running rich....the popping could be the unburnt fuel igniting in the exhaust. do you smell fuel in the exhaust?
could it running lean cause popping? the '75 fuel pump may not be enough for the 3.2, just shooting in the dark though

[crashr]

Hi Guys,

Two things that I forgot to mention in my orginal post:

1) The gas that was in the tank was 94 octane, but that was three years ago, who knows how good it is now. (However I initially ruled this out because of the fact that the popping happens on acceleration, if it was bad gas I would have thought that it would have been more random)

2) I do have something that appears to be part of the vacuum line system not fully hooked up. Please see thae attached pic. I am not sure what this is or where it mounts on the car, however I only have two lines instead of the potentially three vacuum lines running to it. Could this be causing the issue? What is the third line suppose to hook up to?

[Jim Smolka]

Had a trouble with a 3.2 missing under excelleration. Cleaned up the flywheel speed and reference sensors.

Also, check the distributor. Often, these will have some rust on the inside.

[Esel Mann]

Pardon my elbonian, but WTF is that hemmoroid on you air intake inlet?

Is that stock? I do not ever recall seeing such a tumor on a stock engine. What is it for? Nitrous?

Carlton

[crashr]

Who shot who in the what now? Sorry on my inlet. Are you talking about the partly unfolded peice of electrical tape? If it is that is what I am asking? What hose is suppose to attach to it?

[Esel Mann]

The unfolded electrical tape appears attached to some sort of object (the one just to the left of the oil cap). This object in turn appears to be attached (by some means?) to the air intake snorkel.

It is this object which I have never seen attached to the air snorkel of a 3.2L engine.

Is it perhaps not attached and simply it is simply brought forward from the back to be able to take a picture of it?

[crashr]

correct, it is not attached to anything except for two hoses which appear on the opposite end of the tape.

What is this object? What is its purpose?

What is the purpose of the air snorkel, and where is it suppose to be attached. I may have place it on the mysterious object out of sheer stupidity!

[crashr]

Someone must know what that is? Is it from my old 2.7?