The sluggish gear change in my 2000 P38 DSE improved a lot after an oil and filter change but on Friday it reared its head again. I did a 90 mile round trip mostly in 3rd gear at no more than 40mph, no acceleration, no power on the slightest incline and top gear only downhill when I managed to get it up to 50mph; it wouldn't get over 60 even on a downhill motorway. I began to wonder if it might be an electronic rather than mechanical fault, several ECU functions like the trip computer and alarm don't work properly, so I plugged in the OBD scanner and guess what, no power at the socket. Fuse 33 is ok, there's no obvious corrosion or damp in the socket, so where next? Could it be fuel starvation? Should I change the fuel filter? Any advice most welcome.
brianp38dse
Well-Known Member
There is a temp sensor on the head that can effect the gearbox, there are three fitted on your head but I cant remember which colour is the one.
it could also be the valve block in the gearbox sticking adding some Lucas transfix can help but takes time to work its magic some 1000k + and a couple of oil changes with lucas
what obd are you using as there are only a couple that will talk to the diesel.
it could also be the valve block in the gearbox sticking adding some Lucas transfix can help but takes time to work its magic some 1000k + and a couple of oil changes with lucas
what obd are you using as there are only a couple that will talk to the diesel.
No I wasn't aware of that, I'm surprised in that I thought it was an absolute requirement of the USA market that all cars be OBD compliant, but perhaps not that surprised that Rover Group technology should be so insular. Looks like it's a trip to my local garage with RoverTest equipment.
I think the scanner is called an HH Advanced but the issue is not talking to the diesel, it's not picking up any power from the socket. It does work on my 2003 MG TF.
brianp38dse
Well-Known Member
Where about in Bucks are you as there are a few off us on here with the right equipment to read these motors.
Of the three sensors on the head, I had to change the second from the front of the head back. I had intermittent torque converter lock up problems. I had found the sensor had started to weep and had become loose in the brass fitting. After changing it all was good in the world. 
Wazzajnr
Well-Known Member
Obd2 in Europe was from 2001.
You should be able to read engine codes as the requirement only covered the engine ecu although if it's a diesel the requirement was a few years later and the diesel ecu is not, as far as I know, obd2 compliant.
If you're trying to read the gearbox ecu, I very much doubt the cheap scanners will do the trick.
You should be able to read engine codes as the requirement only covered the engine ecu although if it's a diesel the requirement was a few years later and the diesel ecu is not, as far as I know, obd2 compliant.
If you're trying to read the gearbox ecu, I very much doubt the cheap scanners will do the trick.
With luck the problem is solved, I nursed the car to the workshop on Monday, RoverTest did its thing and it's the air mass valve stuck. When it's unplugged the car runs perfectly, if with a lot of smoke, and hopefully tomorrow I'll get the call that a new one has been fitted, and that I'm about £400 lighter. Thanks everyone for your contributions.
If they are saying it's the MAF sensor on a diesel they are talking bollocks, it has nothing to do with how engine runs, it is for feedback of exhaust gas ingestion when EGR is operating. The reduction in air flow through it when the EGR valve opens tells the ECU how much is being ingested . The ECU then modulates the EGR valve to control ingestion subject to the combustible air required to service the present throttle power demand. Although one that has failed completely may confuse the ECU. Get them to check if the EGR valve is sticking open. If that's what they mean fair do's, but nothing like £400.00.
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Bloody egr valves are more trouble than they are worth!! The later electronic versions are really troublesome... Mines blanked and had the vacuum tube cut and hidden out of view for the mot... But then I've the older type, not so easy now without deleting driver from the ecu... unless they are talking about replacing the egr valve??
unless they are talking about replacing the egr valve??
What did they do?
Unless the MAF sensor had a serious short circuit that was confusing the engine ECU that is highly unusual. The MAF sensor under normal circumstances plays no part at all in engine management.
Jesus, I wish I had the ability to physically check around an egr valve and tell you what was going on inside!!
I think somebody had the wrong idea about what was up with it!!
I think somebody had the wrong idea about what was up with it!!
So do i. Maybe the MAF was duff and had a short that was confusing the ECU putting EGR on when it should not have been active. Anybodies guess but sounds iffy to me. EGR is not supposed to be active at idle, on acceleration or under load. Sounds like it was on all the time to me. Wonder how much it cost him.
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It cost me just short of £400, which was more than a little annoying because I asked him to do nothing until I made a decision whether to spend money on a repair or scrap the car but he went ahead and ordered the part. My reading of the workshop manual is that the air mass meter, as it was described to me, plays an important part in telling the ECU when to open or close the EGR, so with it not fuctioning the EGR was wide open all the time hence poor starting, no acceleration, no pulling power and top speed of 44mph at 3000rpm. Much better now.
