Help!

smac61

Founding Member
May 28, 2002
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17
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Driving to work Friday, after about 28 miles of normal cruise, I was coming out of a 45 zone, car was in third gear. I increase speed to 55, and just as the trans shifted into OD the car started to shudder as if it had a spark miss. Running pretty ragged for the next mile to work, and the check engine light came in. As I stopped I could hear what seemed to be valve tapping similar to what you would hear with low oil level (oil level and pressure were fine). Checked all the spark plug wires, no arc. Noticed that my wide band was showing a little lean (around 16), so tried adjusting the AFR with the PMS. I could tell a difference but the problem was not corrected. Pulled the codes and got a 65, bad act sensor. Replaced the ACT sensor today, no difference. The code 65 also returned.
I don’t know if the tapping started at the same moment that the car started to run rough. And although it started the moment the tranny shifted to OD, the condition is present in all gears and at idle. Don’t know if this means anything, but the tapping seems to be from the right side at the front of the valve cover which happens to be near the ACT sensor. Is there possibly something wrong with the #5 valves/rockers causing heat build up in the #5 runner (ACT location)? What the heck is going on?? Little help please!!
 
Yeah, that did cross my mind, but I kind of blew it off since it has that bolt thing that secures it. Maybe the other side though, where it mates up with the engine harness. You're right, I should probably check it. That may explain the ACT sensor code, but not the tapping, right?
 
The tapping can be explained by the 16:1 AFR if the PMS is doing screwing things. Lean fuel and some screwy spark tables is enough to make all the ticking noises you'd like.
 
Ah yes, I see now. At idle I was able to bring the AFR down into the 12's and it seemed to start choking as I added more. Tapping was still there throughout the adjustments. I think I will pull those connectors and give them a fresh coat of grease just to be sure. If that doesn't do it, I guess I'm off to the mechanic. Thanks for the input!
 
No hard acceleration at the time. Normal 5 AM commute. Probably the result of pokin it one too many times (3 years and 40,000 miles on the engine). Not that I would ever do that! I guess its just one of those things.
 
smac61 said:
No hard acceleration at the time. Normal 5 AM commute. Probably the result of pokin it one too many times (3 years and 40,000 miles on the engine). Not that I would ever do that! I guess its just one of those things.
Yeah it happens :shrug: Good luck getting it fixed and the car back on the road :nice: