irobertson

So the day before my first DE, I take the car out for a quick run and...

I had a brief cut out (like a quarter second) just as I'm pulling away from a light. Then it happens again in 1st, then a while later at low RPM in 2nd.
Next thing that happened was it started revving at a stoplight all by itself, bouncing from 1500 to 2500 and back again. As soon as I touched the throttle, it stalled. Thankfully it started right back up again.
I've pulled the ICV and I'm going to check that tomorrow when I have a meter.

Thought I'd toss this up here though in the mean time and see if anyone else has any input or suggestions.

Thanks

theiceman

Did you replace the head temp sensor when you did your rebuild ? Try jumps ring . It out with a paper clip once it's warm. Might be a quick short cut to get you through IDS

irobertson

Yes, I did put a new one in when I did the rebuild. I check that anyhow and see if that makes thing better. ICV checks out OK, seems to move freely, and measures 20.5 and 19 ohms. Tnx Clive

theiceman

have you driven it much this year yet , I don't suppose it could be water in the gas or anything like that ?

irobertson

No, it;'s really quite predictable. If I let it come down in second to under 2K, then try to accelerate, it happens just about every time. If I'm above 2K, no problem. It seems like is has to do with the transition from the idle circuit to the throttle body. I'm going to check the operation of the idle switch too, maybe that is sticking as I open the throttle.

oldskewel

Just a thought - could it be a dead spot on your barn door air flow sensor's potentiometer?

The clue (before real diagnostic testing) would be that it occurs at the same air flow rate (so high RPM in first and lower RPM in 2nd makes sense).

If it sounds feasible, search on here for the simple electrical tests you can do to confirm it.

irobertson

Update, I took the car to a DE on Saturday which was a 3 hour drive each way, plus all the exercise of actually doing the DE, and didn't have a single issue. Have had no issues since either. Whatever electrical issue I had seems to have corrected itself. Ghost is back in the closet. I really would have liked to have done something to correct the issue for sure. We'll see if it ever comes back. Thanks for the suggestions guys.

theiceman

It's that farm country gas I'm sure


How was the IDS Ian ? Did it cause you any IBS ?

cairo94507

That's funny. I do hope you can find the source of the problem to prevent a future issue and give you peace of mind.

irobertson

Well, that depends.... Kidding. It was great. The best part was having Yarko instructing me on the skid pad. Plowing around in a circle with Yarko yelling More GAS, More GAS. The hardest part was hard braking with no ABS in the wet, and then trying to exit the box cleanly. I've signed up for 4 of the Mosport DE sessions, but the only one that has space so far is the October one.

When do expect to complete the project?

theiceman

Long block done. I'm thinking may 24 to be on the road.

irobertson

Well damn it if the ghost isn't back. I took the car to Oakville yesterday, and then today leaving Oakville and again all the way through DT Toronto and up the DVP it was acting up. That made for a rather stressful drive. Through observations I have come to the conclusion that it is just simply losing 12 volt power to the ignition system. If it cuts out up around 4K, the tach drops right to zero then bounces back again when she comes back to life. I swapped DME relay, to no effect. Tomorrow I think I'm going to remove and carefully inspect the DME itself.

irobertson

Good to hear.

Irhmsd

Sounds like you have a lead on the issue. Electrical gremlins are the worst. Check battery cables. A bad ground can cause this. Is there any rhyme or reason to it going south when the car gets jolted by a bump or during shifts when the inertia of the engine and Tranny shift?

irobertson

That's the annoying part, I starts happening at completely random intervals. At first is seemed to be upon moderate acceleration, but now it happens at idle, light throttle, moderate or full throttle. I haven't been able to cause it to happen by wiggling anything. I'm also going to check my flywheel sensors, because I saw another thread related to that issue. Hopefully I find the gremlin soon.