High RPM while idle than normal??

[Hussien]

Hello, everyone.

I have a problem with my car (VE L98 6.0L V8 Engine). Yesterday, I started my car and the RPM was high. Normally, the RPM goes down to 580 rev/min when the engine is warmed up, but it didn't go down. It remained at 1024 rev/min. I tried to drive it and it accelerates by itself without depressing on the pedal.

Check Engine Light became ON. I used a scanner tool, the code is P0507. I tried to clean up the throttle body, MAF sensor, and air filter, but the RPM is still high. Because of high RPM, The temperature of the coolant is between 99 to 106 Celsius. It used to be between 89 to 91 Celsius when the idle was normal.

What could cause high RPM at idle?

Thanks.

 

[Hussien]

I forgot to mention that I tried to disconnect the battery for 30 minutes, and it didn't solve the problem. Please help!

 

[Hussien]

Guys, I found a bad hose, I don't know what its name, but the hose from the intake manifold to the throttle body. I think its name is PCV or something. it has something to do with the oil evaporation. could high rpm cause by this bad hose?

 

[delcowizzid]

Yes replace hose.check other hoses while in there

Sent from my C8660 using Tapatalk 2

 

[vr355stroker]

Is that hose shaped like a V and on the driver's side up front .....if so you can plumb a catch can to those fitting's if not....pls disregard :whistling

Just my 2cents

 

[Hussien]

I replaced the bad hose. The RPM is still high. the car is uncomfortable when you drive it because of the high RPM, and it is consuming more fuel,

Guys, I have another car which has the same engine, just tell me what should I replace even if it's not correct. I will not lose money, just taking parts from the other engine.

Thanks.

 

[HEXEM]

Try resetting the ECM. Process below.

ECM reset.
1. Ignition off.
2. Pull ECM fuses. ( In the VE there is one where the battery is (little black box) and the other in the fuse box in the engine bay)
3. Turn ignition on (DO NOT START ENGINE) till the warning chimes sound.
4. Turn Ignition off.
5. Replace fuse/s.
6. Turn ignition on and check that all is OK.

 

[Hussien]

Try resetting the ECM. Process below.

ECM reset.
1. Ignition off.
2. Pull ECM fuses. ( In the VE there is one where the battery is (little black box) and the other in the fuse box in the engine bay)
3. Turn ignition on (DO NOT START ENGINE) till the warning chimes sound.
4. Turn Ignition off.
5. Replace fuse/s.
6. Turn ignition on and check that all is OK.

I tried to do this, nothing happened. The RPM is still high. Do you have any other suggestion?

 

[HEXEM]

I probably should have asked first if you have any mods (engine, exhaust etc) on the car or is it all factory?

Have you checked ALL hoses are connected correctly.

It could be a TPS (Throttle Position Sensor) fault, you can do a reset on the TPS however, you will have a fault code that will need to be cleared once doing the reset. I had to get mine cleared by Holden, not sure what you can do with your scan tool.

To reset the TPS
1. Pull the plug from the side of the Throttle body
2. Turn ignition to on (DO NOT START UP ENGINE)
3. Wait for the error chime on the dash
4. Turn ignition off
5. Reconnect TB electrical plug
6. Start engine, leave it run for normal cold start warm up and see if idle drops after a 1min or so.

Failing this take it to Holden for proper diagnostics and fix.

 

[anarklov3r]

have a look at this, a few potential fixes and description of the problem

P0507 Idle Air Control System RPM Higher Than Expected - DTC Code