Hi All,
Please may any of you offer some help diagnosing my problem?
Really sorry that this is another duplicated thread. I've read multiple over the months but not being fully up to speed on engine parts/function I may not be putting two and two together.
I'll give you a chronology of how it has behaved and everything that I have tried.
- 2016. Failed MOT on emissions. Replaced catalytic converter. Passes MOT. Given back to me and the exhaust acoustics are much louder. On the way home the car cuts out. Find that a vacuum hose has split. Mechanic replaces vacuum hose. Runs OK but still a bit rich.
- Runs OK but loses power at about 2000-2500rpm (particularly going up hill or when carrying a passenger). Then starts cutting out again.
- Take it to different mechanic. 02 sensor and another split hose connector replaced. Put on rolling road - no issues.
- Days before its MOT cuts out on a steep hill whilst stuck in traffic on a hot summer day. Towed home. Fires up but chases idle (exhaust acoustics sound like a revving tank)
- 2017. Failed MOT on emissions. Replaced catalytic converter. Throttle body cleaned and new hose connector replaced on the MAP sensor which had split. Passes MOT and runs beautifully.
- After a few drives the acoustics start to increase again. I find that the new MAP sensor hose connector (straight design) has been slipping off so I replace with an right-angled connector which offers a tighter grip. This helps but still can't find idle, then cuts out after I fire it up, then doesn't start full stop.
- It is now back at the mechanics where the following has been done: 1) New temp gauge and sender, 2) Crank shaft sensor replaced, 3) mechanic says that when he electronically loops out the SPi part of the ECU (excuse me if this is factually incorrect/not possible) it runs better but still not great. He says it will then stall after 5 minutes or so.
- Mechanic has now drawn a blank - he thinks the electronic positioning sensor/signal might be the cause but before he spends more of my money wanted to make sure he's not following an expensive train of thought.
Other info (when I last plugged a code reader in although since then the temperature gauge & sender & crank shaft sensor have been replaced)
- Idle switch Off
- P/N switch On
- MAP Sensor 39kPa
- Coolant temp 33deg C
- Inlet air temp 20deg C
- Ambient air temp 200deg C (I've read other threads and this is a 'forced' value?)
- Throttle pot volts 0.84v
- Lambda 740mV
- RPM 1211
I also should mention that the heater stopped working a while back. Could the water pump be contributing to my problems? Also wondering if the stepper motor could be faulty?
Appreciate you taking the time to read the above! Any help will be hugely appreciated.
Thanks very much.
Matt