Intermittent Engine Miss/Shutdown

Newbie here with a new problem on my VR4. Over the past few days, every once in a while (maybe every 2 or 3 days), my engine loses power suddenly and then within half-a-second runs normally. It's happened when idling, or when going thru the gears (a bit disconcerting when getting on the expressway!), and yesterday it started doing something a little different. I was going up an on-ramp when it bogged down. I pulled over to the shoulder and I kept my foot in the throttle (about 1/3 open), and the motor seemed to "cycle" between 1k and 2k rpm. It would go up to 2k then immediately drop to 1k then up to 2 k then drop, etc. It did this for about 3 minutes, never dying entirely, although I kept my foot on the gas (1/3 depressed accelerator peddle) for fear it would die completely. After about 3-4 minutes of this, it suddenly sprang to life and revved up to about 4k (my foot was still on the gas so it responded accordingly).After that, I drove about 5 miles home and without a problem. I accelerated hard, softly, put it in neutral and let it idle. No problem showed up. I'm wondering of I could have a coil going bad. I don't think it'd be a CPS would it - don't they cause misses at all rpms and then just go dead? Fuel pump relay?

Any ideas would be appreciated. (Car has recent plugs, wires, and I have a ecu capacitor set on the way.)

Thanks

Wayne

 

[Okayplayer]

I would check your intercooler piping. Sounds like you have a cracked coupling or something is loose.

 

[89Mirageman]

My guess is that it's ECU related.

 

I'll pull that and look for "bubbled" capacitors. Any other tell-tale signs of ecu issues I should look for on the circuit board?

Thanks

 

[cheekychimp]

Smell the board. Sounds stupid but a faint fishy odour is as clear tale a sign as the capacitors themselves.

 

[Xcelerate]

Try a boost leak test. Also check for loose wires on coolant temp, power transistor and coils. Do a tune up new plugs and wires. Also replace the fuel pump and do a compression test.

 

[5OF2k]

Sounds sort of similar to an issue I was having when my coil bracket kept coming loose and causing my coils to intermittently short. Might be something worth looking into.

Hope that helps!

-Jake

 

[tonie4ws]

I encountered the same problem.MAF is the culprit,after i changed it the problem is gone.

 

[gvr4ever]

Couldn't the TPS sensor also cause this problem?

 

[JoeDaddy0]

Oddly enough I had the same symptoms as a result of one failing spark plug wire until the wire actually failed. I guessed everything from ignition, ecu, fuel pump as it gave all of those symptoms. That may be why some would think it is a coil.

 

that sounds like a ecu. with a scand tool look at the baro&battery voltage if the numbers jump around its the ecu.