crg53

Most of the time my engine runs just fine, but once in a while it seems low on power/sluggish and it will also develop a mis, and then all of a sudden it is back to normal. Any ideas, your help will be greatly appreciated.

Thanks

Indycam

Have you had the codes looked at ?

crg53

Indycam, nobody here on the island have the hammer, I think maybe a trip to the mainland would be in order. It feels like a loose connection not sure but very annoying. I have another question regarding the CEL; when I start the car the CEL will sometimes stay on for 15 seconds or so, other times not at all; is that normal?

garrett376

Air Flow Meter is the likely cause for your intermittent miss/lag in power.

911URGE

I think Garrett376 is on the right track. Make sure the AFM Wire Harness TSB has been performed.

ilko

The TSB is only for 89 and 90 cars IIRC.

springer3

The only time in over seven years of ownership that my engine did not run great was when I started to have high-voltage breakdown in one of my coils. That problem was intermittent at first. Lots of 964s got new coils recently, and there are numerous posts. The scantool said I had almost every code possible - the electromagnetic interference from the stray voltages does that.

+1 on Garrett's suggestion to check the AFM, particularly if the car was ever over-filled with motor oil.

crg53

Both my coils have been replaced, one about 2 years ago and the second only a month ago. The problem started this spring when I first started the car after 5 month of winter storage. I had done some maintenance over the winter,
new fuel filter, had the injectors out and tested and of cause oil and filter change. First I thought it was a loose connection on one of the injectors, because it was only running on 5 cylinders, then suddenly it ran just fine and did so for over 2K miles, up until lately when the problem showed up again. I have a spare coil, so I will replace the one that was installed 2 years ago to see if that makes a difference.

jimq

maybe critters chewed some wires while in storage?

crg53

I know the problem with critters, but no sign of them in my garage. I leave a few packages of soda crackers in stratigic places, if any critters around they will chew holes in the packages, then I bring out the heavy artillery.

Indycam

Any chance someone will lend you a code reader ?
Or maybe you could buy the thing ?

"I have an extra ScanTool kit. PM me, if you are interested."
Rocket Rob 04-27-2009, 11:39 AM

Shamus964

I recently resolved a hesitation when cold under 4k and other misfire issues by disconnecting and reconnecting the low voltage leads to the coils.

At first I thought one of the coils was dead, but it turned out that it was just corrosion on the leads. I would disconnect them, hit them with some de-oxit and reconnect and make sure that they snap tight on re-connect.

As has been discussed in the other coil/distributor threads, I found that running on only 6 plugs created a serious hesitation when cold and I had to really feed in power when starting from a stoplight to avoid it bogging down. Now she's purring great.

Good luck!

crg53

Thanks for all the input.
I changed the 2 year old coil out for the one I replaced a month ago; keep your fingers crossed, because the car runs just perfect now. Hope I found the problem.
Is there an alternative to the Brasilian made Bosch coils, they seem to be very unreliable.
I would like to check the AFM, but do not know how to do that, any help would be greatly appreciated.

sml

crg53

what was the outcome here please?

crg53

The car has been running perfectly ever since I changed out the coil.