Engine Hesitation

RED95SC

Registered User
I have a 95 AOD SC. At about 30-40 mph and with the SC at around 5lbs of boost the engine seems to hesitate, usually happens only going through town. Its goes away once the speed is over 40 or more boost. I have changed the plugs and wires and fuel filter as recommended by others. What else am I missing? Please HELP!

Andy
 
whoa

i guess you and i are in the same boat, just changed my filter plugs and wires as well

i'm also experiencing low rpm at a stop light and my oil gague
goes down with rpms to about 600 then they both come back up together.

i'm thinking the boost issue (oil pump, vacuum issue?)

i need help to
 
maybe its the same problem...but my oil pressure gauge dosen't dip down at all. The hesitation seems to happen in the summer, it did it last summer and it was almost non-existent in the winter but now its back?? Other than that the car runs great, I don't know what to think.
 
oil issue...
me neither i just might have a clogged oil pump it was rebuilt with new components but hey you neva know

hesitation....
may be the egr valve gets stuck and when that pressure builds up it doesnt flow properly and in the summer since it hot it might stick... i'm just guessing
 
First, describe exactly how it is hesitating. Is it a delay in response time when you press the accelerator, or is it a miss that occurs randomly while holding 5 psi boost?

Next, describe any other abnormal symptoms that you may be experiencing.

At first glance, it seems like this could be an issue related to buildup of heat.. due to the facts that it does not occur in winter or over 40. The first thing that comes to mind that could be affected by this is the DIS module. Perhaps check the heatsink compound which allows it to better conduct heat away from the unit & to the heatsink.
 
that is kinda what mine is doing, just after it is warm though. it has like a miss at low rpm and right around that 5 lbs of boost area. i have changed everything from wires to fuel pump but not the DIS. my prob also might be it has champion plugs in it. i am changing those tomorrow and bringing them back to the rep cause numerous people have told me that are cars are very picky as to what plugs to use.
 
actually it like a skip or miss when the needle goes into boost (5psi) it is like it gasped for air then when the needle drop out of boost it's fine....

but i think i might get a DIS Module from Advance Auto Parts (lifetime warranty) i think the DIS might be old i just got the car and it was rather shall we say very VERY NEGLECTED!!:eek:

Also My oil gauge issue... when i come to a stop, the idle is at about 600-700 rpm i notice the dip to just below 500 rpm

the oil gauge needle, and the rpm needle moves below 500rpm
check gauge light quickly blinks on and off.

then it's normal...wierd
 
That last symptom you mentioned is wierd. An alternator could theoretically cause an idle drop down during a stop.. but I would go to a mechanic and have them pressure check your oil system to make sure you aren't losing pressure.

Maybe something from the rebuild is caught in your oil filter..
 
i have same problem

i have an 90 sc 5 speed that does the same thing if i drive it easy its fine but when boost hits about 5 psi its hesitates and both the boost and tach jump all over till i let off. i had no check engine light on, but it turned out to be my egr was sticking it showed up while running codes.
thanks, rob
 
to njtb

I still have the stumble-
Motor mounts cured the idle drop at stop.
As was explained on this site...the knock sensor picks
up the mounts banging, and advances the timeing.
A real pain in the rea job!
 
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