(Problem solved) Urgent technical help required with abnormal running problem.

[Kirk]

Thread Updated.

 

Quick question, fitted a brand new genuine water temp sensor to a car I have with me currently and it was running great up till last night when it suddenly started playing up and running rich. Now after much investigation today ive concluded its nothing mechanical, timing is on the mark down to the mm, no vac hoses have popped off, the only thing I've found is the temp sensor resistance is 1.83 ohms at 20 degrees C which is slightly below specifications. It should be anywhere between 2-3 according to the manual. Now would this be enough of a difference to cause it to overfuel?

Edited August 17, 2012 by Kirk (see edit history)

[Shane]

You may have this data already, but if not its very useful:http://www.mkivsupra.net/vbb/showthread.php?238522-2JZ-sensor-resistance!

 

Why not stick a small variable resistor in there for now to see if that small difference is whats causing the problem.

[chrispot]

is it running rich with a hot or cold engine? readings that you have got i would have thought would make no difference, if its running rich when hot then do a resistance reading on the temp sensor when hot. I would say you have some other problem thats causing it to run rich, map sensor / 02 sensor / fuel pressure ect.

 

where did you take the temp readings from, on the sensor its self or at the ecu, if you checked sensor might be worth rechecking at the ecu which will eliminate any wiring faults?

 

regards chris

[Kirk]

Edit.

Edited August 17, 2012 by Kirk (see edit history)

[Kirk]

Edit.

 

Problem solved. River of fuel from a faulty nitrous solenoid leaking into the IC pipes causing mass over fueling.

Edited August 17, 2012 by Kirk (see edit history)

[chrispot]

in your description you said " This time I had a surge of fuel come directly around the silicone connector to the TB and it cut out once again." where has this fuel come from? the only place that a std engine gets its fuel from is the injectors.

 

could it be your fuel pressure regulator is at fault, the diaphram inside has gone and the engine is sucking fuel through the vac/boost ref pipe?

 

regards chris

 

ps lets us know what the problem was

[dan294]

The car had a wet nos system fitted. The wiring was disconnected and the solenoids and jets left in place. The jets were plumbed into the IC pipe on the inlet side. The fuel solenoid had been leaking fuel through and it was sat in the inter cooler and the bottom of the IC pipe. He drained it off and it's now ok I'm told.

[Kirk]

Exactly what Dan said. In all seriousness it was a river of fuel. It took around an hour to clean out, cleaned the plugs up and got it going.

 

What through me was the car would idle and rev fine anywhere below 4k but of course it would the ECU is running a closed loop strategy so the lambda see's the fuel and adjusts fueling accordingly. As soon as it strayed into open loop the MAP sensor would demand fuel except there's already fuel in the charge and as you would expect it chokes the engine and killed it. I managed to get myself that worked up with it I forgot the obvious things like that but in my defence I did open the IC pipe once and nothing fell out so this left me confused. After leaving it over night its obviously gathered into the pipe and gave me a nice lovely shower when I removed it.

 

Pretty confident now its working well. Its seen full boost without issue so fingers crossed.

Edited August 17, 2012 by Kirk (see edit history)