V4 Wont Idle

pugtk

Sunday Drivers
Hi All,

I was reversing my v4 type out of the shed a few weeks back and it just started running lumpy and would not idle.

My fuel gauge was low so I assumed it ran out of petrol.

I put about 20 litres into her last night and again the same issue.

It can misfire, backfire and cut out.

Eventually if you do get to start her and rev it to 3-4k and it avoids stalling once its warm it runs ok.

The temp gauge is also erratic.

It has an obd2 port, which ive tried a launch system and the torque pro app, neither could connect to the ecu.

It's almost like an ignition problem, new plugs were fitted, ht leads tested o.k , no loose earths.

I'm wondering those the temp gauge effect the ecu's cold performance?
 
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Just on the diagnostic port side of things, I know this was a cross over year for obd1 and obd2 ports.

There's a green and black connectors under the dash also.

Read online that connecting these will allow you to read codes by flashing lights ( much like old Hondas etc )

Would these need to be connected also to allow the obd2 connection to communicate with the ecu? It would seem a bit strange.

Work away from home during the week, so this will wreak my head until I can get home!
 
So I got my brother to send on a video of the flashing codes (check light)

22- Knock Sensor
23- MAF
31- Throttle Position Sensor
45- Pressure Switch

I can'y imagine all these went at once, so which would be the most likely culprit.

I thought a temperature sensor was the problem, guess not!
 
I would clear the codes and see what it throws up again.

They could be old codes.

Then try it with the maf sensor disconnected and see will it run?
 
As above clear the old codes and see what codes come back and take it from there :thumbsup:
 
I've got the brother to disconnect the battery, so by the time I get home at the weekend she should be reset.

Can't really run her through the reset steps as she's no fully ready for the road just yet.

Must check if there is a 9 pin port under the dash and see if he has a ssm fitting for his launch somewhere if there even is one for that system.
 
Just home today, so having another luck.

After disconecting the battery. Once the black connectors are connected im getting a continious flash.

So the ecu has no stored faults.

Starts up and runs fine for about 30 secs then cuts out

Going to try the tps first
 
Maf tested while running 1v to approx 5v before i lost power

Also a puff of fumes managed to come back out the intake.

Tps meased on ohms off the car from .7v closed to aprrox 5.5v fully open

Going to try temp sensor next

Then have a look at my timing to make sure a tooth wasnt jumped
 
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