Overfueling problem?

[Grizzly]

Hi all.

I\'m having a look at a mates FD at the moment, whats happening is its acting like its on Cold start all the time (Overfueling on Idle (so its lumpy) when you drive it it pops and backfires etc when it comes on First Turbo and it\'s most ovious when the second turbo is just about to spool up but isn\'t, then the Second turbo does its bit and it clears and pulls ok.

To start of it had a Rebuild 18 months ago and i tested it today and its seeing well over 7 bar on each Bath.

I have Changed the Map sensor (for one i know is working of my car), Good plugs (swaped of my car), checked for Boost leaks (found one in the Turbo-IC pipe which was replaced), the air pump has been removed whilst the cat is still in place (but it goes better at high revs so i don\'t think its that), There was loads of cheap Silicone vac pipe all over the place which i\'ve replaced with some Viton i had over from a job (still hate Silicone as its so soft, i could imagen it colapsing with vacume going through it)

After i did all this i noticed it had an Aftermarket Water temp gauge in the car, so when i asked about what sort of temp it runs at i was told "The Temp gauges don\'t work" then it started to rain so i packed up for the day.

Now i\'m thinking along the lines of the Water temp sender being dodgy, i know when they go the ECU goes into limp mode or could think its cold all the time?  The thing is, isn\'t there Three Senders on the Pump housing? does the same one do the ECU and the gauge? If so that may be the Problem?

I have had a quick search and basicly came up with the simalar sort of replys so i\'m intrested to hear if anyone has had the same sort of probelm and what cured it?

Cheers
Chris

[Grizzly]

Out of intrest, how do you test if the water temp Sender is working? does the old trick of Grounding the wire and the gauge flicking over to hot work? or does it not work of ground? (used to work by causing resistance to the ground and the level changed as the Ohm value changed?)

I have also heard of people conecting the Lambda Sensor plug onto the water temp and vise versa?

O yeh this car is Stock (apart from a Cat back and a pair of Filters)

[Grizzly]

I\'ve just been folowing it and there is lets say more than usaly amount of Blue smoke coming out of it too, I would not say its exessive but more at low speed and idle.

[grinder]

im sure the FC uses the water temp for something , so the FD could be the same

im sure you can ground the sendor to check that its working - just check the FSM , im sure it will tell you in there chris

[m4drx]

borrow an apexi and whack it it on it will show the water temp off that sensor. the sensor is located in the filler neck/thermostat housing but you have to remove alternator to get to it. im sure its this though.

the only other place i can suggest is the cold start mechanism which is located on the rear of the throttle body above the tps opposite the bulkhead. it has a coolant hose going to it and a spring loaded thingy on the bottom which goes downwards when it gets hotter, it could be the case that this has a problem but tbh if the screw makes no contact it wont fast idle or anything so i really think it is the water temp sender as its the one that provides the signal to the ecu whereas the cold start is mechanical.

i have every sender from the cooling system and filler neck pipes and cap etc if needed.

good luck.

Tharek

[Grizzly]

Thanks for that,

Is there any way the sensor can be checked off the car? I have one that was working (two years ago when i took it off) but looking at it i guess its not a nice job to be doing twice, I\'m not 100% its not the wiring as well (looks a bit dodgy to me)

I did think about pulling my PFC of and putting it on this car to check but to be honist i\'ve just had it valeted (£150 worth) and its the best its looked for years so i don\'t want to go pulling it to bits so thats a last option if i realy realy must.

Out of intrest, Does the one you have defo work? (have you checked it) If so what would you want for it?

[m4drx]

the only way i know of is the apexi im affraid unless you can wire a aftermarket gauge directly to it etc which invloves stripping wires or removing it anyway.

changing is relatively quick and easy for someone whos done it before but alot of bits need to come off so its a bit tricky for someone who hasnt but long more than complicated as it is straight forward.

the sensor i have came out of my car checked the temperature before and after installing the new one and never went back so definately working.

£15 posted if you need it but check the wiring as you said as the heat kills them esp after 14odd years.

let me know if you need any help mate or just pm me your details and ill send any stuff you need over.

tharek

[Grizzly]

I\'ll have a play with the wiring to it and if i still have no joy i\'ll buy yours of you

[m4drx]

I\'ll have a play with the wiring to it and if i still have no joy i\'ll buy yours of you

no worries mate, only thing to watch out for is the tension of the belt to the alternator as i think it covers the OMP too.

:wave