Runs bad after revving past 3000.
#1
1990 T2
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Runs bad after revving past 3000.
I had my battery disconnected overnite. i connected it and started the engine. After about 10-15 seconds it will run great. Steady 725-750 rpm. But if I rev the engine a couple of times and rev above 3000 rpm, it starts idling bad, raising and lowering between 750-1200, over and over.
If I shut the engine off and disconnect the battery for a few minutes, then restart it, the engine will be back to a good idle until it is revved past 3000 rpm again.
What could be causing this? I can't find anything like this by searching for it.
If I shut the engine off and disconnect the battery for a few minutes, then restart it, the engine will be back to a good idle until it is revved past 3000 rpm again.
What could be causing this? I can't find anything like this by searching for it.
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#8
1990 T2
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I did get it to run a little better by swapping out the leading coil. Now both leading plugs are firing on the mark but the #2 trailing plug is firing 90 degrees or more off the timing mark. The #1 trailing plug actually fires right between the trailing and leading marks.
It doesn't seem to be missing too much when accelerating quickly but misses badly if accelerating slowly. It starts missing around 1800 rpm and seems to even out above 3000.
#9
Nothing to see here.
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What method did you use to test/set the TPS?
Read through this thread if you're not familiar with setting/testing the TPS:
https://www.rx7club.com/showthread.p...&highlight=tps
Read through this thread if you're not familiar with setting/testing the TPS:
https://www.rx7club.com/showthread.p...&highlight=tps
#10
1990 T2
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What method did you use to test/set the TPS?
Read through this thread if you're not familiar with setting/testing the TPS:
https://www.rx7club.com/showthread.p...&highlight=tps
Read through this thread if you're not familiar with setting/testing the TPS:
https://www.rx7club.com/showthread.p...&highlight=tps
Maybe I should start a new thread, since the problem now is not the problem that the thread was opened with.
#11
1990 T2
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Maybe I should start a new thread, since the problem now is not the problem that the thread was opened with.
The engine will idle at around 800-850 fluctuating. The timing is set dead on with the L1 plug firing on the first mark but the T1 plug fires almost in the exactly same place, within a degree or 2. The L2 plug fires at the first mark but bounces between the first mark and a couple of degrees above the second mark. The T2 plug will not cause the timing light to fire at all.
What would cause this? CAS, ECU, gremlins.
The engine will idle at around 800-850 fluctuating. The timing is set dead on with the L1 plug firing on the first mark but the T1 plug fires almost in the exactly same place, within a degree or 2. The L2 plug fires at the first mark but bounces between the first mark and a couple of degrees above the second mark. The T2 plug will not cause the timing light to fire at all.
What would cause this? CAS, ECU, gremlins.
#12
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I was reading some old posts and now I'm thinking that all -or at least most- of the timing mark problems are probably being caused by an older/cheaper timing light.
I'm going to pick-up a new light and recheck the marks and see if the problem still exists.
I'm going to pick-up a new light and recheck the marks and see if the problem still exists.
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Placing them Near the spark plugs is the best bet...They are a finicky thing.
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