[7.62x39]

Spark plug wire harness? Car Sounds really rough when it starts reving back n forth to 3k and 2k rpm

 

[6Speed]

Spark plug wire harness? Car Sounds really rough when it starts reving back n forth to 3k and 2k rpm

Hard to know with that limited info. I'm thinking this sounds like a throttle body issue from what I've read in the past on "rev hunting" cars. Try cleaning the throttle bodies first. If that doesn't work my next suggestion would be to look into plugs and coils.

 

[The Technician]

What year or model is the car? Probably either a coolant temp sensor or more than likely a sticky throttle body or bodies. It is computer controlled but if something is causing one to hang open or one is closed or mismatched it will be off. Or a vacuum leak. Depends on mileage to.

 

[7.62x39]

Hard to know with that limited info. I'm thinking this sounds like a throttle body issue from what I've read in the past on "rev hunting" cars. Try cleaning the throttle bodies first. If that doesn't work my next suggestion would be to look into plugs and coils.

Yea I clean the throttle body’s already, they are going bad but I think it’s the lower camshaft wire/sensor by the headers or it could be my coolant line maybe that’s rite at the end of coolant tank. it didnt start idling like this till I was messing with those two things

 

[7.62x39]

What year or model is the car? Probably either a coolant temp sensor or more than likely a sticky throttle body or bodies. It is computer controlled but if something is causing one to hang open or one is closed or mismatched it will be off. Or a vacuum leak. Depends on mileage to.

It’s a 04 gallardo

 

[The Technician]

Without reading the sensors and seeing whats going on its hard to say. With what you said about the sensors it could be that but unless you want to start throwing parts at it its going to cost. I have a scan tool for it but I'm clear across the US on the other side. Unless you want to pay for my flight lol

 

[robgreg75]

Could be a vacuum leak and the car isn't know what to do with it.

 

[RMR]

Vacuum leak, secondary air injector system is bad, bad fuel injector, bad pump...the ECU is seeing a lean condition, adding fuel and raising the rpm to compensate. Could be throttle bodies as well but your best bet, as others have mentioned, scan for codes. That'll at least get you pointed in the right direction. If it's really rough at cold startup your fuel trims could be way out of whack which could be an issue with an injector OR elsewhere.

 

[FL_Beachman]

Hard to know with that limited info. I'm thinking this sounds like a throttle body issue from what I've read in the past on "rev hunting" cars. Try cleaning the throttle bodies first. If that doesn't work my next suggestion would be to look into plugs and coils.

Agree-dirty throttle body is the first place i would look and just because it looks clean does not mean it is, even the smallest of debris will cause issues. Remove the hose and manually open the butterfly make sure to wipe down the butterfly also, use brake fluid or alcohol wear gloves, i used a really stiff tooth brush first -it looked clean was amazed when i wipe it down how dirty it really was. take your time and really work it clean, i spent a few hours on mine, the idle bounced around when it was hot and after cleaning everything in the air system including new air filters and air intake hoses problem went away, it does not really help if you just clean the throttle body and the filters/air box/hoses are a mess, they need to be cleaned too.