MAP sensor

Hi Doug,
did you check the MPS?
A MPS with vacuum leak would lead to very rich mixture.

But check the resistance of the cylinder head temp sensor at the ECU connector, too. The other reason for rich mixture...
Check at the connector, not at the temp sensor, otherwise you wouldn't detect a wire connection problem.

Regards
Norbert

Good morning Norbert,

I'll check the cylinder head temp sensor next but I thought these sensors where just an overheat sensor in that as long as the temp didn't go above a specific value the engine continues to run.
I have accidently left this disconnected before and the engine won't even start I didn't realise that it affects the mixture.
I got 2 MAP sensors from Canada and they both make the engine behave the same, really rich, so maybe both don't hold vacuums I will also test these, I did electrically test them but not for vacuum.
I'll feed back on the above and let you know how I get on, thanks again Doug.

Hi Doug,
the temp sensors, the cylinderhead sensor more than the air temp sensor, are essential for 'calculating' the mixture.
When the cylinder head sensor is disconnected, the mixture is enriched as if the temperatures would be extremely low, the mixture is about 3 times richer than it should be when the engine is warm.

You could replace the sensor in the case it is defective by a simple resistor, about 200 Ohms (1/4 Watt is sufficient) against ground for a test.
Then the ECU 'calculates' the mixture for a warm engine.

I'm sure the disconnected sensor is the reason for your probs.

Regards
Norbert

Hi,

I was out for a family event so I could nto answer earlier. Engine temperature sensor is essential for mixture. If missing, your mixture can be three times as rich as normally. It heavily affects.

New MAP sensors should of course be checked for vacuum leak, no renewal of potting and original screws / rivets.

Volker and Norbert,

You are both absolutely correct the cylinder head temp sensor wasn't connected properly so I've replaced the connectors and reconnected it and the resistance measured at the ECU connector is as per the table and it now runs much better at idle, as I would expect.
I also checked the 2 replacement MAP sensors that I sourced from Canada for vacuum, 1 is good the other leaks down a bit too quick, not as fast as the one tested in the video clip on here but faster than the other, so the good one is fitted.
I managed to drive it down the road yesterday evening too but it won't pull under high load situations, it just misfires and splutters, could this be FI related or is it more likely to be the HT ignition system causing this?

Many thanks again gents for all your help.

Hi Doug,

it sounds more like wrong ignition timing if it misfires.