Went to parts house today to get some touch up paint. As I was pulling in I noticed the Jeep was idling at around 250-300 rpms. Which I feel is low. Got home and now it’ll idle around 700-800 rpms. But if I rev it up and let of gas the Jeep dies. Anyone ran into this problem? Check engine code P1494?
Idling low and dies if you rev and let off throttle
- Thread starter smurf
- Start date
When you rev the engine and the engine dies or idles at low RPMs could be indications of a dirty or malfunctioning Idle Air Control solenoid.
Suggest you remove the IAC, clean the throttlebody throat port for the IAC and the seat inside the cavity where the IAC plunger operates.
Suggest you remove the IAC, clean the throttlebody throat port for the IAC and the seat inside the cavity where the IAC plunger operates.
The larger rubber hose in the 2nd picture that goes from the Charcoal canister to the Purge valve has a crack in the hose where the line plugs into the Purge valve... This could give you CEL for the Evaporative Emissions system.
Not sure about the electrical connector which might be for the A/C Hi Pressure switch....; really have to see in those pictures.
Not sure about the electrical connector which might be for the A/C Hi Pressure switch....; really have to see in those pictures.
There is no need to physically remove the IAC (idle air control module) to clean it. In fact, if you keep it mounted and clean it by spraying throttle body cleaner into the throttle body while the engine is at idle rpms you'll get a cleaner IAC and cleaner air orifice that the IAC's plunger moves in & out of.
Aim the cleaner spray at the tapered Idle Air Control Passage Inlet slot, that is where the IAC takes all of its air in through.
Just make sure that you only spray the cleaner into the throttle body while the engine is at idle rpms. Raising the engine rpms any will cause the cleaner to bypass the IAC. The engine WILL die when you spray the cleaner in at idle rpms, that is because the cleaner is flooding the IAC which is a good thing. Just restart the engine and do it again and again until you've gotten around 1/3 of the can through the IAC.
Aim the cleaner spray at the tapered Idle Air Control Passage Inlet slot, that is where the IAC takes all of its air in through.
Just make sure that you only spray the cleaner into the throttle body while the engine is at idle rpms. Raising the engine rpms any will cause the cleaner to bypass the IAC. The engine WILL die when you spray the cleaner in at idle rpms, that is because the cleaner is flooding the IAC which is a good thing. Just restart the engine and do it again and again until you've gotten around 1/3 of the can through the IAC.
This is all great advice. 250 rpm would read zero on the tachometer. The first dot at zero on the tach is 250, second is 500, 750 and then 1000. The engine doesn't run between 250 and zero so Jeep left that first dot off the gauge. It's not a big deal but when talking about idle rpm it helps when you read the numbers as they are.
JB,
The reason why I recommended removing the IAC; a lot of times I have found there is debris or varnish build up on the seat inside the cavity and the disc of the IAC solenoid plunger....
C
Imma replace that hose. That would make sense as to this Jeep was built without AC
I found an older thread where you had explained this and read all nine pages haha.
Had this exact thing come up yesterday. Jeep wouldn't start unless I gave it lots of gas while cranking, and then would die if I didn't keep giving it gas. My IAC looked exactly like yours, but I still plan to follow Jerry's plan and shoot some cleaner up in there while it's mounted.
Yeah, I’m not sure what it is. I cleaned IAC and reset engine code. Still idles the same but hasn’t thrown light yet. I know it will with time. Not a clue why it started idling so low. Could be fuel pump? Idk
Jerry I don’t have any throttle body cleaner. But I do have some mass air flow cleaner? Think this is about the same stuff? Safe to use?
Yes you can use the mass airflow cleaner on your throttle body or IAC but you can't use throttle body cleaner on mass airflow sensors. Mass airflow sensors are damned picky/fussy SOBs.
Be sure to use a little more of the MAF cleaner, it's not quite as aggressive as TB cleaner is. I'd use no less than 1/3 of a can.