Okay here's the scoop,

When decelerating withing the 5-10 mph range the car idles pretty low, shakes moderatly, but does not stall, and continues to shake untill acceleration. I havent recieved a service engine light at all, but know that the light works. The hoses seem to be fine, and never having expierence taking off the plenum and runners wondering if maybe the valve is just stuck, or possibly the soliniod is bad, but wouldnt i get a light is either were bad ? (by the way i dont have a code scanner) Nonetheless im curious if this is even the problem, any ideas ? Also what is the going rate for the valve, checker told me 110 bucks, and 47 for the soliniod, do these prices sound right ? Any ideas out there ?

 

My first guesses are dirty throttle body and carbon build up, or sticking IAC..

one way you can test the egr valve is unplug the vacuum hose and plug up the valve with a cap and go for a drive..if the problem is gone, theres a good chance its related to the egr system.
I paid around 50 bucks for my egr valve from a local car quest store..its a a/c delco brand.
However, I have a vette so Im not sure if your system is slightly different and uses a diff valve.
Is your TPI system speed density running a map sensor?
I wasnt sure if the F cars switched over in 90-92 to speed desnity as the vettes had done...thanks for any info..just trying to learn more as I go.



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1986 Vette Coupe,auto, alum. heads,40 over,crane cam,3.73 Gears,The usual Mods..
Had an 86 Bird before..want to get another F car again!

 

the f-bodys switched over to spd density in 90

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91 z28 lb9 5 speed - hooker 1 5/8 headers - high flow cat- full 3 inch exhaust - home made ram air - tpis airfoil - dual chamber flowmaster - Stage 2 Jet Chip and 160 stat - 8 mm Msd plug wires - 55,000 v hypertech coil/rotor/distrib. cap - Mac. White face gauges - lots of sound system crap...