3100 engine bogs down

Hello guys

I am having a problem with my 94 skylark 3100. I need fresh set of ideas on this one. The engine runs good I know that for fact. But it's been siting and will not throttle up. It idles good but when you give it gas it falls flat on it's face and bogs down. I have replaced both the fuel pump, filter and spark plugs, no changes. Any ideas ?

Hello guys

I am having a problem with my 94 skylark 3100. I need fresh set of ideas on this one. The engine runs good I know that for fact. But it's been siting and will not throttle up. It idles good but when you give it gas it falls flat on it's face and bogs down. I have replaced both the fuel pump, filter and spark plugs, no changes. Any ideas ?


Could be the ignition coil or the fuel injectors. Maybe the air filter and charcoal canister are due for a change. It could also be a vacuum leak in the PCV pipe.

I forgot to mention in previous post that it starts harder than it should. I did put some fresh gas in it, and that didn't seem to help any. I ran a scan on it, shows no trouble codes.
Yes I will check the air filter. I know it's good but a rat or bird might have a nest up in there. Good thinking Tom. I was thinking that it could be the mass air flow sensor. I can't remember if it has one. Will have to check. I work on so many different cars it's hard to remember. I've also had some one tell me clogged cat converter. I hate to cut it if off and still have the same problem. Would like to look at other things first. I've also been told that it's the fuel pump. I doubt that since I just replaced the pump and the filter.

I would get the ign module checked, many parts stores can do this.

Is the ignition module built in to the coil pack on this one? I just found out about auto parts stores testing ignition modules this year. Advance and Auto Zone can do it here locally. I had no idea they could do that. That is definitely easy and worth checking. Thanks

...don't forget the old fuel filter.

The PCU/ECU needs the right signals for the Air/Fuel mix during the cold start, or choking condition.
Suspect -
1) Unmetered Air leaks from PCV, or EGR systems.
2) MAF/IACT cleaning.
3) Check & clean throttle plate.

If you suspect a plugged catalytic converter causing air problems, do a back pressure test using the upstream O2 sensor hole and a compression testor guage.

I replaced the fuel pump and fuel filter already, too bad that wasn't the problem. My father in law runs a Chevy garage. He said to check for clogged converter by removing the o2 sensor completely and see if that changes anything. I really think the clogged converter thing is unlikely. If you hold your hand over the muffler pipe, the pressure feels like it's un obstructed. It just seems like some stupid sensor to me. But I haven't found what it is yet. It's been sitting idle for the last 2 years and that's when the problem started. It ran perfect previously.

A compression testor in the upstream 02 sensor hole should only read a few psi.

The MAF sensor is a metering signal device, it tells the ECU/PCU how much air is going into the Intake, it could be a false signal without a code.

I always like to try cleaning the MAF/IACT sensor with CRC cleaner, befor a new replacement.