Truck revving up and down by itself

[a80crewza]

Okay, so I started my truck up this morning and the engine (1kz) revs up and down by itself? Didn't notice it after it got warm. So it's not a faulty speedo. Could it be a vacuum leak? A cracked hose? (Ive recently put it a manual boost controller).

[Jerry]

could be early signs of an ecu fault, the caps in them go, how much is it revving?

[a80crewza]

could be early signs of an ecu fault, the caps in them go, how much is it revving?

Not much, maybe between 600-900rpm.

[pressy]

hi it sounds like the air con, does it have air con and does it work? sorry for the possible dumb question?

[a80crewza]

Yeah its got air con and it works, I can't see how it would be the air con as it wasn't on when the revving up and down occurred. And when I did put the air con on, no revving happened.

[curly12]

Yeah its got air con and it works, I can't see how it would be the air con as it wasn't on when the revving up and down occurred. And when I did put the air con on, no revving happened.

Dry contacts in the switch, bit of rain after a few weeks of dry, old pos, warm weather???

Mine decided to turn the horn on last sunday at 5 am after one day of rain................. my nieghbours reckon I am a hard bastard to wake up

[a80crewza]

Yeah, it has been warm here, then it pissed down the other night..

Could you please explain what you reckon it could be

[curly12]

Yeah, it has been warm here, then it pissed down the other night..

Could you please explain what you reckon it could be

Aircon switch needs to be taken apart and crc or w40 sprayed in it to free it up

[a80crewza]

Yeah, it has been warm here, then it pissed down the other night..

Could you please explain what you reckon it could be

Aircon switch needs to be taken apart and crc or w40 sprayed in it to free it up

Okay, where can I find the aircon switch?

[curly12]

Yeah, it has been warm here, then it pissed down the other night..

Could you please explain what you reckon it could be

Aircon switch needs to be taken apart and crc or w40 sprayed in it to free it up

Okay, where can I find the aircon switch?

On the dash???

[kbjj]

Okay, where can I find the aircon switch?

On the dash???

Holy farkin jebus

[Crash bandicoot]

Okay, where can I find the aircon switch?

On the dash???

Holy farkin jebus

classic

[a80crewza]

Is it the dash switch your talking about Or the air con pressure switch??

[curly12]

:lol: Is it the dash switch your talking about Or the air con pressure switch??

Sigh, I feel so old some days..............., There is no power sent to the aircon pump unless the switch is activated

[benorange]

just to throw you off a bit. mine does the same randomly but it not the aircon pump as i had the belt off. mine was played with before i got it had the dump pipe added and the pipe from intake to exaust removed and there is also oil coming from something up top at back. it also lacks power sometimes. just havent been able to get it off road to look at yet.

[a80crewza]

Just disconnected both the batteries to reset the system and that fixed the problem.. for now. Must be the ecu.