What happens at 3500 rpm?
#16
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Just my .02 so use as you see fit. In my experience the problem is likely with the primary side of the ignition, not the secondary (like the wires no offense) if the tach. is "freaking out" too. If it has a dead spot in the airflow meter it's easy to catch. Put a voltmeter on the signal wire coming out of it, ground the other end, and turn the key on. Take a screwdriver (or whatever) and push the meter through its range of travel and see if the voltage increases linearly or not. If it's bad in a certain spot the voltage will momentarily drop.
I've diagnosed a bunch of bad bosch ignition modules before and have come up with a funny but fairly reliable way to do it. They frequently start to fail when hot (under the hood, like sitting in traffic) possibly explaining the intermittent failure. When I had a car start acting up and it felt like the ignition etc. and I was suspicious of the unit I would shoot a little cold water on it and see if it suddenly started running better again (like instantly). If so it's bad then. Kinda funny I had an old bimmer that had one go bad when I was like an hour from my home once. I rigged up the windshield washer hose to spray on it. Every time it started stuttering on the way home I bumped the washers and it would clear right up.
I've diagnosed a bunch of bad bosch ignition modules before and have come up with a funny but fairly reliable way to do it. They frequently start to fail when hot (under the hood, like sitting in traffic) possibly explaining the intermittent failure. When I had a car start acting up and it felt like the ignition etc. and I was suspicious of the unit I would shoot a little cold water on it and see if it suddenly started running better again (like instantly). If so it's bad then. Kinda funny I had an old bimmer that had one go bad when I was like an hour from my home once. I rigged up the windshield washer hose to spray on it. Every time it started stuttering on the way home I bumped the washers and it would clear right up.
#17
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It was...the Ignition Control Unit mounted on the inside right fender. Tried all the suggestions except for the ICU and finally picked one up from 928 Intl in December (on sale too!). Just swapped it out and like magic she hums through all the rpms - no hesitation, no breaking up at 3500 rpm.
Thanks everyone for all your suggestions and help, especially Hacker-Pschorr for being the first to point this out.
Thanks everyone for all your suggestions and help, especially Hacker-Pschorr for being the first to point this out.
#19
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No, I got very lucky - it was during the 1/2 price sale at 928 Intl - around $75.00 if I recall correctly.
I see we have almost identical cars! Mine is an '82 auto as well in the same color. I don't know the true miles however as my odo gear is gone - that's my project in the next week. Should be a riot!
I see we have almost identical cars! Mine is an '82 auto as well in the same color. I don't know the true miles however as my odo gear is gone - that's my project in the next week. Should be a riot!
#20
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No, I got very lucky - it was during the 1/2 price sale at 928 Intl - around $75.00 if I recall correctly.
I see we have almost identical cars! Mine is an '82 auto as well in the same color. I don't know the true miles however as my odo gear is gone - that's my project in the next week. Should be a riot!
I see we have almost identical cars! Mine is an '82 auto as well in the same color. I don't know the true miles however as my odo gear is gone - that's my project in the next week. Should be a riot!
I've gone into my pod twice now, it's not that bad. It can get confusing putting it all back together. Try to remember that the cluster gets screwed to the right side of the pod before you put the cluster and pod up on the dash. The left side gets screwed together after it's up on the dash. Weird design.
And be careful with your cluster after you get it out of the pod. I think I may have maligned a couple of my gauges while resting it face down on my legs.
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#22
Chronic Tool Dropper
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^^^ What he said. Plus you can drive a sheet-metal screw into the temp gauge face to the right of midpoint. Keeps the car from overheating. Simple yet for some odd reason an underutilized repair method.
#23
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... I've diagnosed a bunch of bad bosch ignition modules before and have come up with a funny but fairly reliable way to do it. They frequently start to fail when hot (under the hood, like sitting in traffic) possibly explaining the intermittent failure. When I had a car start acting up and it felt like the ignition etc. and I was suspicious of the unit I would shoot a little cold water on it and see if it suddenly started running better again (like instantly). If so it's bad then. Kinda funny I had an old bimmer that had one go bad when I was like an hour from my home once. I rigged up the windshield washer hose to spray on it. Every time it started stuttering on the way home I bumped the washers and it would clear right up.
Brilliant!! I wish i'd thought of that when the TFI module on the Scorpio was crapping out intermittently. That was an instantly-dead-in-the-water failure. It doesn't scare me too much to head for the berm of the freeway across a couple of lanes - signals, lights and DO IT - but it was a different matter for my wife.
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Five minutes with hood up and the car would start right up and run fine for a while, minutes or days. A snap to fix, a royal PITA to Dx.
#24
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The pod has been something I've been wanting to get into for a while but didn't want to do it when I knew I would have to stop and not be able to get back to it for a few weeks/months. It sounds like it may be a challenge to check everything out (odometer gear, dash lights, volt meter, clean connections, handle the printed circuit board carefully - I believe the '82 is very difficult to find used and especially new). Should be interesting though.
#25
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One of the least expensive and most effective repair options yet discovered for this common problem!![thumbup](https://rennlist.com/forums/graemlins/thumbup.gif)
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