Starting problem

ok got a 87 xj takes 5-15 seconds of cranking b4 it will start then it revs up to 2000rpm then goes down and stalls if i keep it at 2000rpm's for 10-15 seconds then let off it will stay running but when i hit the gas it tries to stall out then revs up and when i was leaving a parking lot the other day i was in first with gas pedal halfway down and it acted like i put it in fith gear from a stop but it was definatally in 1st. pls help need to get this thing fixed b4 friday

its got the 4.0 4x4 5 speed peugot tranny with 200,000 miles

wow, holy run-on sentance... at least use some comma's.

when was the last tune-up?.... and has it been running fine untill recently when this started... or is it new to you?

i would start w/ the idle air control valve... disconnect and remove it, clean the pintle of the valve, AND the passageway it closes..... if its a new-to-you jeep, and an 87... you got lots of catch-up work to do...

start w/ a tune-up, --new cap/rotor/plugs/wires-- maybe even a new o2.
then make sure your vacuum hoses on the top of the motor arent plugged up...


welcome to the board

its labeled here as an 'air stepper motor', its on the side of the throttle body



as cheap insurance, also replace the ground strap that connects the engine block to the firewall, and your battery cables if they are iffy...

does the truck shake at idle? that would kinda indicate you have a cylender not firing right...

hard to say, where to start.....
get going if you want it fixed by friday

also, be gentle with the stepper motor, it can be fragile.

If you don't know when they were last replaced, at least pull a spark plug and take a look at the condition and the gap. It should be .035", but if they are eroded to .050", replace them. Throttle Position Sensor can definitely cause these symptoms. There is a adjusting procedure for RENIX that has been covered many times.

i wouldnt start with o2, the o2 sensor doesnt even come into play until the car is warmed up

thanks guys i am gonna try cleaning that sensor and checking and regaping the spark plugs. and where is the TPS located and is there a way i can test it??

i have only had this jeep for about 2 weeks. and it had sat for about a year without being driven while sitting it was started once in awhile