Weird problem
04-29-2017, 03:49 AM
#1
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Car: 92 rs daily driver work in progress
Engine: 3.1 , 204/214 cam
Transmission: 700 r-4, b& m megashifter
Axle/Gears: I want a posi with rear discs
Weird problem
Doesnt matter full or 1/2empty gas tank...
I come to a light or stop sign , rpms drop really low then pop back up in a few seconds. Battery gauge dips to almost 8 then up to 12.
New plugs cap rotor. No vac leaks . ran seafoam less than 50 miles ago.
No codes. E month old tps and idle control sensor.
New fuel pump. New fuel filter. No cat.
I've pretty much fired the parts cannon at it.
Can't figure anything else out.
It idles aroun 1000 and cruises at 65-70 at just under 2000.
I come to a light or stop sign , rpms drop really low then pop back up in a few seconds. Battery gauge dips to almost 8 then up to 12.
New plugs cap rotor. No vac leaks . ran seafoam less than 50 miles ago.
No codes. E month old tps and idle control sensor.
New fuel pump. New fuel filter. No cat.
I've pretty much fired the parts cannon at it.
Can't figure anything else out.
It idles aroun 1000 and cruises at 65-70 at just under 2000.
04-29-2017, 09:39 AM
#2
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Car: check
Engine: check
Transmission: check
Re: Weird problem
With replacing the IAC along with likely having had the battery disconnected for some of the work, an idle learn is required.
There are several threads here on how to do it. Search using my name as the author.
RBob.
There are several threads here on how to do it. Search using my name as the author.
RBob.
04-29-2017, 03:32 PM
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Car: 92 rs daily driver work in progress
Engine: 3.1 , 204/214 cam
Transmission: 700 r-4, b& m megashifter
Axle/Gears: I want a posi with rear discs
Re: Weird problem
Already did idle relearn.
Even on a full tank. Acts like it is outta gas. 2 month old fuel pump. Maybe a bad map sensor from the parts store??
Even on a full tank. Acts like it is outta gas. 2 month old fuel pump. Maybe a bad map sensor from the parts store??
04-29-2017, 05:23 PM
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Re: Weird problem
New MAP too? Were all the new parts installed in trying to fix the idle dip issue? This makes a difference in how to go about troubleshooting the problem. If so it may be the ECM is bad.
RBob.
RBob.
04-29-2017, 05:32 PM
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Car: 92 rs daily driver work in progress
Engine: 3.1 , 204/214 cam
Transmission: 700 r-4, b& m megashifter
Axle/Gears: I want a posi with rear discs
Re: Weird problem
New map even upgraded ecm and chip per tuned performance
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05-06-2017, 03:08 PM
#9
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Car: 92 Z28
Engine: Ramjet 350
Transmission: T-56
Axle/Gears: 3.23 Torsen
Re: Weird problem
I would check for any vacuum leaks , check your sensor that's on the power steering high pressure hose, check iac of course and also yty to wait it out , drive your car for more then an hour. When u reset the battery it does that the first 30 min or so the it eventually fix itself
05-13-2017, 09:10 AM
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Car: 92 rs daily driver work in progress
Engine: 3.1 , 204/214 cam
Transmission: 700 r-4, b& m megashifter
Axle/Gears: I want a posi with rear discs
Re: Weird problem
No codes no speedo issues.
But tuesday no oil pressure drop .oil level perfect coolant perfect. Not redlined engine at all. All a sudden got an engine knock.
Mechanic said new engine. Either rod or main bearings just failed. Car still drives but loud knocks very bad above 2000 rpm. Idle is almost not noticable.
But tuesday no oil pressure drop .oil level perfect coolant perfect. Not redlined engine at all. All a sudden got an engine knock.
Mechanic said new engine. Either rod or main bearings just failed. Car still drives but loud knocks very bad above 2000 rpm. Idle is almost not noticable.
08-05-2017, 07:21 PM
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Car: 92 rs daily driver work in progress
Engine: 3.1 , 204/214 cam
Transmission: 700 r-4, b& m megashifter
Axle/Gears: I want a posi with rear discs
Re: Weird problem
Rod bearings were fine. Replaced them cam lifters timing gears and chain cap rotor and plugs and wires. Getting it all buttoned up hopefully by monday. See what happens from there.
