Idling issues.

[lynden]

Hello everyone.

I've got some slight idling issues that are more of a nuisance than full blown problem.

'96 D1 176K miles- When starting from cold, the idle will stay a little high. You'll drive a ways and when you come to a stop the idle is 200-400 rpm too high. If you sit at the light/stop sign it'll come back down. Its a little annoying and somewhat unsafe in that you have to use a lot more brake at a light.

The worst issue is once the truck is warm. After warmed up, the idle runs really low. The truck runs great when you're giving it gas. Once you let off though it idles very low (down to 500 or 400 rpm). Sometimes the idle will run so low that the truck will die. This is more than annoying. I'm having to drive w/ 2 feet- keeping a little gas while braking w/ right foot.

Anyone have these issues in the past? I think I read a thread a looooong time ago that people were having problems when their battery was old. Mine is pretty old but have no problems w/ starting or running accessories so I don't have any reason to suspect my battery is running low.

Thanks in advance!

 

[fishEH]

Hello everyone.

I've got some slight idling issues that are more of a nuisance than full blown problem.

'96 D1 176K miles- When starting from cold, the idle will stay a little high. You'll drive a ways and when you come to a stop the idle is 200-400 rpm too high. If you sit at the light/stop sign it'll come back down. Its a little annoying and somewhat unsafe in that you have to use a lot more brake at a light.

The worst issue is once the truck is warm. After warmed up, the idle runs really low. The truck runs great when you're giving it gas. Once you let off though it idles very low (down to 500 or 400 rpm). Sometimes the idle will run so low that the truck will die. This is more than annoying. I'm having to drive w/ 2 feet- keeping a little gas while braking w/ right foot.

Anyone have these issues in the past? I think I read a thread a looooong time ago that people were having problems when their battery was old. Mine is pretty old but have no problems w/ starting or running accessories so I don't have any reason to suspect my battery is running low.

Thanks in advance!

I just had this problem. Turned out to be a bad gas cap. Take off your gas cap and see if your problems go away.

 

[singingcamel]

Check for a bad collapsed vaccum line.

 

[96discoI]

Not too sure about cause but my symptoms are similar. I have done the IACV and swapped in a MAF but it still is acting sick. will post updates soon

 

[syugg]

Anybody figure out a solution to the idling issue? I have similar symptoms as the original poster. Swapped out the IAC, smoked tested for vacuum leaks (none identified), and swapped out the MAF for a used one (helped a little but still having issues).

 

[syugg]

Swapped out the ECU with two other ECUs, replaced the fuel pump, checked fuel pump connector, and replaced gas cap. Took it to two rover specialist in the area and they are at a loss as well. Any ideas? I'm at my wits end with this truck!

It's a '96 D1 with 225K miles.

 

[listerdiesel]

Have you checked the oil separator in the rocker cover breather pipe? Affects to D2, probably the same on a D1, but worth a quick look to see if it is sludged up and blocked.

Peter

 

[ERover82]

In what way does the gas cap cause issues?

 

[robertf]

In what way does the gas cap cause issues?

purge valve is supplying air instead of fuel vapor.

 

[stu454]

Throttle position sensor, maybe??

 

[Danger rover]

Throttle position sensor, maybe??

Ditto. A bad Vehicle speed sensor will give you some of the same symptoms as well.

 

[listerdiesel]

Regarding the fuel cap, there's a bit in RAVE about leaking caps affecting the purge system, and by default that impinges on the inlet manifold where the valve exits.

Peter

 

[smrover1]

Having idle problems here also. Had base idle reset about a month ago. Drove it yesterday rover started bucking and rover is stuck on high idle again about ready to give up on her and get diff vehicle

 

[ksmtaw]

Have you checked the codes from the OBD? My very early 94 disco has a box under the passenger seat that shows a two digit code when something is wrong. I had surging and high idle issues and it told me it was the MAF. I bought a reconditioned one for 80 dollars and the fixed the problem and I cleared the code.

 

[96discoI]

Just found the problem and solution. High idle after all of the usual suspects were either replaced or cleaned and tested. Drill adjustment holes in the tps so it can be adjusted for idle. The older models have the slots but the 96 does not. It comes with two holes and no adjustment so you need to drill them out so it can be tilted for idle. Believe me i tried everything and this works. Must be something the land rover mechanics union came up with so they can be assured that frustrated owners come in as soon as they get a new tps installed. good luck. hope it helps someone. BTW I had no codes, nothing. just a problem getting the idle to stop going too low and too high. I even tampered with the idle set screw with little result. This tps needs to be adjusted mechanically not electronically.

 

[Butch]

Just found the problem and solution. High idle after all of the usual suspects were either replaced or cleaned and tested. Drill adjustment holes in the tps so it can be adjusted for idle. The older models have the slots but the 96 does not. It comes with two holes and no adjustment so you need to drill them out so it can be tilted for idle.

I had the same issue and drilled slots in the TPS to adjust it. That worked for just a few minutes until the high idle returned. I took it to a shot and they had to reset the voltage on the TPS because it was too low.