Engine popping & stuttering during acceleration- any ideas?

[Kaleid]

Maybe someone can diagnose this issue as it's always happened every once in a while but today was especially bad- car drives ok with "normal load". When accelerating hard or giving it gas to go up an incline I have what sounds like a Tito Puente timbale solo coming from the air cleaner/exhaust- I can't be sure exactly. Sounds like random pops- as this happens, the car seems to stutter a bit before continuing to accelerate. Engine is a 2.2S with MFI- anyone have a similar experience or know what this could be? Could the car be running too lean? MFI pump was dialed in about 3 years ago when the car was restored.

Thanks,
Marco

[Steve@Rennsport]

Hi Marco,

First question is: Did the engine run like this after restoration? If it ran well,..there are some things to do here.

It sounds fuel-delivery related, however I'd check out the ignition system component first before progressing to the MFI system. Make certain your plugs, wires, points, cap & rotor are all in perfect condition. Make sure the distributor is advancing correctly. Failure to do these important steps first can become a "red herring" when investigating fuel faults.

After that, I would confirm fuel volume & pressure delivery from the electric pump. Plugged in-tank or rear filters can create problems for the electric and mechanical pumps. Measure fuel pressure and volume at the filter console.

If the fuel tank has ANY water in it at all, its time to drain the tank and flush it with clean fuel. Water is heavier than fuel and does a nice job of obstructing passages in the whole system.

Its important to mention that our cars need to be stored with a totally full fuel tank to prevent condensation!!!

Please let me know what you find with all this.

[304065]

Tito Puente? I've been listening to him for years and I think he's FABULOUS

Any competent Porsche driver tracks faster if brakes come smoothly

Air filter compression loss plugs dwell timing fuel pressure injectors belt correlation smog.

NEVER DEVIATE FROM THIS SEQUENCE

[Kaleid]

Steve & John,

Thanks very much for the advice- Steve, car was running amazing after resto- this is a problem that has been slowly showing up a bit more often. Yesterday was pretty bad. Ignition system seems to be ok on all fronts. Will check fuel system as best I can with my limited knowledge of it. I can say that within the last year or so there has been an increase in fuel smell in the cabin. Would any cracks in the tubing of the fuel venting system or otherwise be a contributor to the problem? Just wondering if these two issues could be possibly related.

[304065]

Cracks in tubing= Fireball waiting to happen

This will help

http://www.flatsixaddiction.com/peli...ure_Adjust.pdf