Fired up the rover for the first time today.

Started out ok... then rpm climbed to 1500 on its own, started to settle down to 1000, then shot up to 2, 3, then 4000 rpm. Then I shut the car off.

Fault codes:
121 (assuming P0121 ?)
"Load Monitoring (Air flow/to Throttle Angle) Fault - Value not plausible. Fault present and static."

So I'm thinking this could be the MAF sensor? The value (with car off) reads at 20 kg/h. Then i took it out, blew air on it, no change in value. Unplugged it... stayed at 20 kg/h. Is this wrong?
Many months ago, I cleaned the MAF sensor with MAF cleaner.

I tested the TPS sensor, it seems to work correctly, going from 0 to 70% with the gas pedal on the floor.

I think it could also be the idle air control motor, but I don't see any tests for it. Again, many months ago I cleaned it thoroughly, it had a ton of gunk and carbon in it.

 

I had some of the same issues with mine but didn't have a code reader handy at the time. I loosened the throttle control cable till it was just about loose. I also took off the idle air control valve hoses one at a time and covered with my hand to check n see if that was it. I then loosened the throttle position sensor and found my culprit. When I had the throttle body powdercoated, I rewound the spring too tight and it caused that issue. I took the throttle body apart and loosened the return spring one time and then put it all back together. I then adjusted to throttle cable and now she purrs like a kitten. The way I tested the throttle position sensor was to unscrew it and the rotate while the engine was running to see if that turned the rpms down and that's how I knew it was a screw up on my part. Hope this helps you jeff.
Jason

 

Thanks jay, but I don't think thats my prob.

I ran it again, and was able to successfully break the engine in @ 2000-2500 rpm for 30 mins.

But there's something wrong with the EMS / idle throttle.

Whenever I applied a tiny amount of throttle, the RPM would rise and stay there, even after returning pedal to 0%. Via Live Data, the "Desired Idle RPM" and the "RPM" are always the same. Add a tiny bit of throttle, it rises, and stays there. It got a little high at one point so I pinched off the IACV hose which made it manageable.

I figured as long as the engine was running well at the correct RPM, with good temp and pressure, I should continue to let it break in.

30 mins @ 2000-2600 rpm
Temp: 195 F. Never higher
Oil Temp: 195
Oil pressure: 17-19 psi
Clean exhaust
No tapping, everything sounded great

Just this weird ECM issue. Anyone have a clue? I tried unplugging the IACV, and the MAF, no change. Where is the engine even getting its air from?? SAI pump was not running. I did do the "Reset adaptive values" via the Lynx. Maybe that messed up my ECM?

 

Jason, you may be onto something. I will pull the throttle body and see if theres anything weird. I've never taken off the TPS sensor though.. hmm maybe when cleaning the throttle body gunk got stuck in there.

Since the RPMs can go to 4k+ at 'idle', I can't imagine its a vacuum leak. Only the throttle body could deliver that much air, right? Maybe the SAI could, but I would get codes if a valve were stuck open.

 

Just an idea here as I had something similar happen last week when I was bleeding the cooling system. I was raising the tank to run out the air at the tee. When I reset the tank it somehow kinked the return hose from the manifold to the tank (my throttle body heater is bypassed). Did not notice it but when I fired up, ran fine then idled up to about 1100 and would not return. I noted the kink, raised the tank to straighten out and boom, back to normal. Not sure why that would make a difference but it surely did. If by chance you bypassed the throttle body heater, the flow still needs to get back to the system. Maybe nothing but...

 

My disco is non sai equipped but I would just take the 2 bolts off off the tps n rotate it with it running to see if you can get the rpms to drop n go from there.

 

I was able to get the rpms to return to normal by whacking the TB with a screwdriver, so it must either be the tps or the return spring. Sensor seemed to test ok with a multimeter. Weird since my tb is welll cleaned

on another note, after switching from 10w30 breakin oil to rotella T 15w40 I have have a pretty load tap. Not sure yet if the oil is to blame. Psi is also 3-5 lower, idling around 10-14 which seems low

 

It's always something trivial man and glad you got it fixed. It drive me nuts when mine was done but then I got to thinking about the throttle body and how it was disassembled and powder coated and took it apart and resolved it but a good wack does the trick a lot of the time. Hope that ticking goes away man

 

Well hey, its not fixed quite yet, unless you'd like to ride under the hood for me with a screwdriver and whack the TB when I honk the horn =)

 

its a long way from bama to Seattle but I'm sure I still have some "friends" I could stay with. And only if it's in the express lane. Not dealing with the regular interstate.