Hi Guys, can anyone shed any light on the problems I'm having with my 2003 4200 cc. I've recently replaced all four lambda sensors on my car, since which time it's ceased to run properly. The sensors by the way are Bosche from Lambda Power of Sheffield with the correct part numbers. When cold it starts ok but once it's warmed up it's very reluctant to start. It fires then stops or it fires and runs but the RPM fluctuates for a few seconds and then it just dies. If I "catch it " when it fires it can be persuaded to run but it's far from happy. Once it's on the move it drives ok . Has anyone any thoughts on this, does it need to be hooked up to an SD2 machine? Or have I gone and ruined it?
Lambda Sensor Woes.
- Thread starter atreyu1
- Start date
CatmanV2
Member
- Messages
- 48,772
It might. Are you sure your OBDII is working? It seems astonishing it's not showing even a pending fault on a stalling engine. But there we may well be.
If it is working, then my guess would be SD2 etc is required
C
jluis
Member
- Messages
- 1,703
Did it start after you replaced the lambda's?
Lambda's are emissions equipment and as such are mandated by law to be readable via standard OBD2 protocol.
Your bluetooth adapter will be able to get a reading on the lambda values and fuel trims and you can try to interpret that data.
Lambda's are emissions equipment and as such are mandated by law to be readable via standard OBD2 protocol.
Your bluetooth adapter will be able to get a reading on the lambda values and fuel trims and you can try to interpret that data.
I replaced all four Lambdas last Wednesday and yes it started ok. I took it for a short run and it seemed to be ok but not as good as it was before the change. Last Thursday I drove the car for approx 150 miles on the motorway. When I left the motorway it began to run so roughly that I thought it was going to stop. I stopped the engine as soon as I could but on restarting the engine was still running badly but only at idle. The symptoms are these. It fires straight away upon turning the key, the revs rise and immediately die and the engine stops. It will continue to run if I "catch" it with the throttle, it then runs but the revs fluctuate from about 12-1300 rpm to very little. Yesterday after a run which got it thoroughly warmed up it was idling at well over 1000 rpm. It only does this when warm, there is no cel light and nothing recorded on the OBD 11. I've decided to re fit the old sensors to return it to it's original state. If that doesn't cure it then I'll have to look further.
I've just started the engine after it being stood all night. It fired straight away and ran normally. But, as it warmed up and the revs started to drop it started to run very slightly unevenly. I let it run a little longer then stopped the engine. I tried to start it again and it fired instantly but immediately stopped. Tried again and caught it with the throttle and it kept running but with the revs fluctuating again. It eventually settled down and idled normally, sort of. Now where's me spanners and the old sensors?
GeoffCapes
Member
- Messages
- 14,000
A possibility is that your cats have collapsed. Sounds very similar to what happened to my 4200 when they collapsed.
CatmanV2
Member
- Messages
- 48,772
Because P1602 is listed as low battery voltage.....
although other manufacturers use it for knock sensors
C
The battery is good so I don't think it's that. I've looked at the parts diagrams at Eurospares but can't find a knock sensor. Does it have another name?
It looks like a trip to see Marios at Autoshield. See if his SD2 machine can come up with something. At least it's running so it can be driven there.
It looks like a trip to see Marios at Autoshield. See if his SD2 machine can come up with something. At least it's running so it can be driven there.
Yes I've tried doing a battery re set several times but it doesn't make any difference. Before I fired it up this morning and after I'd changed the Lambda sensors I did a battery reset and let the engine run for 10 minutes to sort itself out. It didn't work, it's just the same as before. I don't think I can do anymore as I'll just be guessing so it's a trip to see Marios. I've come to the conclusion that the Lambda sensors were a red herring. My changing them is probably not related to this fault. It's purely coincidental.
Well the problem has been solved. As I said the new Lambdas were a red herring. The fault was simply that the rubber hose between the throttle body and the MAF had developed a leak thus drawing air in and freaking out the ECU. So now having cured the air leak it's running very well which just goes to show how easy it is to jump to the wrong conclusion. All I have to do now is to re fit the new lambda sensors.