88 3.2 911 - Hit gas, nothing happens , intermittent...

[EMJ]

Cruising along at speed, downshift, hit gas, car bogs down, no response, misfires. Pull over, hit accelerator for a few seconds until I hear it rev again, then I take off again like nothing happened. This occasionally happens at the light, hit gas, nothing happens. Have to feather the throttle until it revs up again and I take off. Completely intermittent but usually happens on an up shift or downshift at highway speeds. Car does NOT stall, just no response when accelerator is depressed.

Been happening for several months. I’ve just replaced the spark plugs and spark plug wires. Still happening. I’ve unplugged the 02 sensor and tested it that way. Still occurring.

This problem was happening last year and the car sat for 6 months. Put in a new battery, replaced a faulty negative battery cable, and drove the car for 2 months and this issue never happened again until recently. Any ideas what can fix this issue? Car drives with no issues for days at a time then this issue just happens completely intermittently.

Thanks.

[cabmandone]

If a new battery cable took care of it for a while I think I'd move to checking all the ground point connections, specifically the transmission ground strap and the grounds at the intake runner. It could have been coincidence that the negative cable fixed it but it's worth a look at the ground points.

Could also have a cracked solder joint in the DME causing an intermittent problem. Seems to have been a few cases of that lately.

[Porsche 935]

Mine did that, found crack in large vacuum line between 2 metal fittings going to brake booster in engine compartment. If engine torqued hard enough it opened up a vacuum leak. Normal driving car was fine.

[EMJ]

Originally Posted by cabmando

Could also have a cracked solder joint in the DME causing an intermittent problem. Seems to have been a few cases of that lately.

Checking the DME for cracked joints is next. Had this issue 15 plus years ago. Soldered them up and never had the intermittent stalling issue I had at the time again. I’ll also check the ground points. Thanks.

[EMJ]

Originally Posted by Porsche 935

Mine did that, found crack in large vacuum line between 2 metal fittings going to brake booster in engine compartment. If engine torqued hard enough it opened up a vacuum leak. Normal driving car was fine.

Thanks. I’ll check for this - makes sense. Only problem is that sometimes the issue happens at the light when I give it gas and the car’s not under load.

[EMJ]

Anything else to check to fix this issue?

[proporsche]

sound like a vacuum leak check you air flow meter boot clamp.

Ivan