Ok, so I guess it must be ignition and not trans??
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From: Illinois
Ok, so I guess it must be ignition and not trans??
when floored my 88' xjs shifts at about 4500rpm. I thought the governor was set bad or something but today I decided to warm up the car and rev it. This is what happens when I floor it in park. It's only getting to about 5k maybe and then drops to like 4-4.5k. I know the vacuum advance is bad but this signal more of a centrifugal advance issue? If it was the secondary coil it wouldn't make it that high?
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From: Pacific Northwest USA
Are you still on the original dual coil system?
If so, if the secondary coil is failing one of the symptoms is inability to rev. Usually the stumbling starts at more like 3500 RPM but, still, it's something to think about
Cheers
DD
If so, if the secondary coil is failing one of the symptoms is inability to rev. Usually the stumbling starts at more like 3500 RPM but, still, it's something to think about
Cheers
DD
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From: Illinois
Yep dual coil Lucas. I replaced the primary this past summer but didn't touch the secondary. This doesn't really seem like a stumble though? It's like it hits a rev limiter.
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"Stumble" wasn't the best choice of words.
"Inability to rev", as I mentioned, is closer to your description of "rev limiter".
Try replacing the #2 coil or using a single DAC6093 coil. You might get lucky!
Cheers
DD
"Inability to rev", as I mentioned, is closer to your description of "rev limiter".
Try replacing the #2 coil or using a single DAC6093 coil. You might get lucky!
Cheers
DD
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From: Illinois
Which is better? Or recommended?
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Most go with the single DAC6093.
"Better"? I dunno.
But it's easy and simple.
Watch out for too-good-to-be-true prices. Lots of junky coils floating around around there.
Cheers
DD
"Better"? I dunno.
But it's easy and simple.
Watch out for too-good-to-be-true prices. Lots of junky coils floating around around there.
Cheers
DD
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I'm willing to try it... as long as it's not super pricey. If I'm already halfway there with replacing the primary then I'll prob go that route. I haven't looked at prices yet. Trying to keep multiple classics going is an ordeal.
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I am with Doug on possibly the secondary coil. BUT this can also be a symptom of the gearbox or TC starting to go home. Try a flash stall test, if the thing will not go to 2700rpm with the brakes hard on in drive (just floor it for a second, no more) the box is going home.
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I am with Doug on possibly the secondary coil. BUT this can also be a symptom of the gearbox or TC starting to go home. Try a flash stall test, if the thing will not go to 2700rpm with the brakes hard on in drive (just floor it for a second, no more) the box is going home.
But sitting in park and revving shouldn't be a gearbox issue?
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Yes it could be, as some bits in the trans are still turning. My mate whose gearbox went hoe in a really big way had similar but worse symptoms. try the flash stall, if it will not go near 2700 you might have found something.
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Ugh that would suck. Ha
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I will give it a try on Friday. I'm thinking I'm going to change the secondary coil with the same coil I got for the primary. Quick question, what's the best "sealer" for the HT lead on the secondary coil?
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Greg
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Well I did the brake "stall" and it revved up just fine. I unplugged the secondary coil and it revved right to 3k rpms and stopped. So could it be the secondary coil just isn't as powerful as it was? Or do they just go bad with no in between?
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If you disconnect the secondary coil the typical and expected result is what you've just described: the inability of the engine to rev past xxx-rpm ---usually around 3000-3500.
Cheers
DD
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If you disconnect the secondary coil the typical and expected result is what you've just described: the inability of the engine to rev past xxx-rpm ---usually around 3000-3500.
Cheers
DD
Cheers
DD
Yeah that's what I was expecting to happen... with it connected I'm not getting it to rev past 5k... so could this be the secondary coil just not powerful enough anymore or more of an vacuum or centrifugal advance issue?
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From: Adelaide Stralia
Coil more than likely, but the list is there, vac, doubtful, but your market has some crazy plumbing, we got 1 hose.
Distributor mechanicals, of course, always a possibility if not service in the last 2 years.
Fuel flow/pressure not there at the top end, doubtful, but has to be checked.
Distributor mechanicals, of course, always a possibility if not service in the last 2 years.
Fuel flow/pressure not there at the top end, doubtful, but has to be checked.
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Coil more than likely, but the list is there, vac, doubtful, but your market has some crazy plumbing, we got 1 hose.
Distributor mechanicals, of course, always a possibility if not service in the last 2 years.
Fuel flow/pressure not there at the top end, doubtful, but has to be checked.
Distributor mechanicals, of course, always a possibility if not service in the last 2 years.
Fuel flow/pressure not there at the top end, doubtful, but has to be checked.
I'll start with the coil because I have done the distributor stuff and fueling stuff this past year... the distributors vacuum advance is bad(diaphragm is gone, no vacuum) I do know, but also not exactly sure how it works in all honesty?