Rb20Det R32 Missing At Full Throttle

[bunnyfart]

Hey guys,

I recently did a turbo upgrade and everything was fine for a couple of weeks (just a bit rich). Driving home from spectating Powercruise i was getting on the highway and when i pushed the throttle in, it gave a small pop and then started to miss under full throttle.

The car has a Stinger EMS ecu, GTR injectors, GTR fuel pump, Yellow Jacket Coil packs.

So far i have checked/cleaned the plugs (covered in carbon), Taped the coil packs, checked for vaccuum leaks, checked the fuel maps, used a multimeter on the ignitor (wouldnt read anything on ohms)

I have searched this forum and many others for possible causes and solutions and so far have come up with nothing.

Any help would be appreciated, even if you have a spare ignitor/AFM around Brisbane that i can test to rule some things out would be awesome.

Edited September 17, 2012 by bunnyfart

[DVS JEZ]

Try another set of coilpacks,

Try gapping the spark plugs smaller.

[bunnyfart]

Used multimeter on coil packs and getting 1.9 ohms on all of them. The ignitor isn't giving a single reading in ohms, but if it was totally busted it wouldn't fire in the first place

[DVS JEZ]

Try another set of coilpacks,

Try gapping the spark plugs smaller.

[bunnyfart]

Trying some tomorrow, ill report back once it's done

[GH05T]

how do you know its rich,

could be a lean pop, i had the same fault and it was my fuel pump, lost rail pleasure at higher revs or under allot of load.

[bunnyfart]

Extremely black smoke and i can almost see the fuel coming out of the exhaust

[bunnyfart]

Massive thanks to SIFTY32 for letting me test his ignitor and coil packs. Nothing changed when i put his on so that rules them out. I ran a data log on my ECU and when i had my foot to the floor with no load the TPS was jumping from 100 (full open) to around 70 - 80 (not full open). My thought process is that the TPS is telling the ECU that my foot isnt to the floor when it actually is.

Is there a decent way to test the TPS with a multimeter?

[DVS JEZ]

Do u have an aftermarket throttle body?

I have had 2 cars lately that have had freeplay between the tps and throttle shaft.

Use a multimeter between the Signal wire and the earth wire.

Should read around .5v closed and 4.5v open completely

[bunnyfart]

standard throttle body. Used the multimeter on the 2 wire and got 1.9 ohms but when i started to move the throttle butterfly it made the multimeter turn off until it was returned to closed.

I changed it to V and got 1.0 on closed and again it turned off when it was opened

Edited September 19, 2012 by bunnyfart

[DVS JEZ]

Theres 2 plugs on the TPS, try the other plug

[bunnyfart]

Ok, it seems my missfire has been solved by disconnecting my aftermarket water temp gauge from the 2 wire sensor.

Its running really well now with better fuel consumption and able to rev really easily.

Can anyone explain to me why the water temp sensor would cause such a massive issue with my car?

[DVS JEZ]

Unless they have wired it incorrectly and interfering with another sensor.

Hows it wired in?

[bunnyfart]

It was wired into the 2 wire ecu sensor not the 1 wire dash gauge sensor.

My guess is it was earthing the positive wire and making the engine stay in closed loop (rich) mode

[DVS JEZ]

I never understand people that wire things in without researching.

Yes thet makes perfect sense as the coolant temp sensor is very sensitive to voltage. It even runs its own seperate sensor ground with only a few sensors like TPS and CAS.

Glad u found the issue