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Discussion Starter · #1 ·
I've got an inconsistent problem of surging and stalling with my '86 740 (non-turbo). I'm low on cash, so as much as I'd like to throw new parts at it, I have to hold out until some definitely breaks, or I can diagnose the problem. Sometimes it stalls on takeoff from a stop, and sometimes it surges at stop, or at steady highway speeds. Fuel pressure regulator? TPS or Mass Air Meter? EGR? Is there a way to test before replacement? Thanks in advance for any help!

Ollieboy
 

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The first thing I would do is clean the throttle body and idle motor first.
 

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Let me know how you make out.Most of the time that is the problem.
 

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Discussion Starter · #6 ·
Cleaned quite a bit of **** out of the TB and as much as I could reach out of the manifold without removing it, and the idle motor didn't look too bad, but sprayed it out good. The wife says it seems better, we'll see, I guess. BTW, what does the coolant temp sensor have to do with idle and driveability? I/ve seen it referred to in other posts. Thanks a lot for help, and I'm sure it won't be the last time I ask for it!
 

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The coolant temp sensor has to do with the engine computer and fuel delivery.When the car is cold it gives the engine more gas.When it is warm it gives less.
 

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Discussion Starter · #8 ·
OK, the coolant temp sensor must be fine then. The guage reads what it should, and it starts and idles OK. My wife has had zero problems today, even in heavier than usual stop and go traffic. Hopefully that's the end of it. Thanks for your info.
 
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