High idle at stops and wants to die after first fired up in the am after 1 minute run

This all started a week ago but once first fire up the 95 xj 4.0 in the am cold mornings here in pa it runs fine for about 1 miunte does smell a little fat unburnt fuel out the tail pipe then after that 1 miunte pull out onto the road give her some gas and dies for like 5 to 10 seconds doesnt stall but gets really close clears up and never does it again. couldnt tell ya weird right. does it every day

Also has a tad higher idle now at stops while slowing down from a crusing speed. Once you get to that stop after 5 seconds of sitting there the idle fianlly does come back down to normal.

As for stuff done. New IAT, TPS, IAC, MAP, 02, bosch injectors, Accell coil, cap, rotor, wires, e3 plugs gapped a little larger than stock.

Any ideas thanks guys. Nots sure how old the Crank postion sensor is but what else could do it. i have checked all vacuum lines no leaks that i see.

one possibility is a leaky injector. were they new or used.

sounds like the IAC is sticky. they get gunked up after a while, and will stick in the cold. you could remove it and clean it, or just swap it out

nope the injectors were brand new bosch fuel efficent spray not the old jeep pencil type wasted fuel spray. the IAC is new from jeep maybe ill just pull it and check it, so far any other ideas

just pulled the iac and replaced it still doing it, fuel pressure was checked this morning with key on not running it is 38 39 psi and while running it is 31 32 and when she goes into that stall in the morning when its cold fuel pressure doesnt change it just wont run for like 15 seconds after she first startes and that 1 minute goes past.

intake gasket/vacuum leak? Rich mixture on cold start is by design, maybe as things warm and the ECU begins receiving valid info, the program isn't effective at richening up to compensate for a small leak until the O2 sensor reaches 600* and it's readings are used to adjust mixture.

Ya know what that sounds possible i did just install a pacesetter header back exhuast i think pace setter is junk but i really didnt know until installed it.

They gave me a paper gasket what is a good exhuast manifod gasket to install?? felpro, or a copper one or what thanks paper gaskets are junk arent they

my vote is for intake leak. i have had those symptoms twice... once it was the fuel injector o-rings gone bad and then more recently i replaced a cracked header, and somehow the intake/exhaust manifold bolts loosened and was allowing air in. an easy way to test for this is to take off your intake airtube, and put your hand over the throttle body. if it dies then its not a leak, but if it keeps on truckin then there is a problem somewhere. hope this helps

g

iam going to pull off my 95 intake anyways and install a 2000 4.0 intake next weekend, so what gasket do you recommend?