2007 gti se missing

[Jmperry1018]

the 4 tec engine runs a little rough. I have drained the fuel, cleaned the tank, changed the two filters, fresh 93 octane, new spark plugs. after the first run, a whole tank full, ive checked the plugs and they looked normal dry with black dust, engine is having a little miss.

 

[POPPS]

Try disconnecting a plug coil one at a time to see if the cylinder fails..and if you find one...change it with another cylinder to see if the problem chases the bad coil...
Pull the rail,,unplug your coil packs,,,turn it over...and see what kind of spray you have...maybe a sticking/dirty injector,,,just some ideas.

 

[Jmperry1018]

Try disconnecting a plug coil one at a time to see if the cylinder fails..and if you find one...change it with another cylinder to see if the problem chases the bad coil...
Pull the rail,,unplug your coil packs,,,turn it over...and see what kind of spray you have...maybe a sticking/dirty injector,,,just some ideas.

And thanks for that I’ve done it and no change took out each one used a 9 volt battery etc.

 

[Jmperry1018]

And thanks for that because that’s what it came down too. Cleaned and reinstalled injectors using a 9 volt battery to open them up.

 

[POPPS]

Apologies,,,I overlooked the "black dust" comment....normally the plugs of a good running 4-tec are very light brown,,, seems like too much fuel being injected?
Pull the rail...put the key in,,,see if an injector leaks,,.
Could even be a failing sensor telling the ecu to inject fuel when it should not...

 

[Jmperry1018]

Apologies,,,I overlooked the "black dust" comment....normally the plugs of a good running 4-tec are very light brown,,, seems like too much fuel being injected?
Pull the rail...put the key in,,,see if an injector leaks,,.
Could even be a failing sensor telling the ecu to inject fuel when it should not...

Great idea as I feel there’s room for improvement

 

[POPPS]

I believe there are resistance tests that can be done on the sensors?..I don't know them off hand,,but they will be in the manual....even,,have a look at the trouble shooting section of the manual.

 

[Jmperry1018]

Great idea as I feel there’s room for improvement

So no leaks for sure. What sensor would that be

 

[POPPS]

Its like a car really,,,tps...mass air flow sensor,,,I know theres a bunch of them,,,get into the manual...can you post a post of the plugs?

 

[POPPS]

I have the 4tec manual..in my ipad,,,.and will dig into it under "trouble shooting" section after supper...

 

[Jmperry1018]

Plugs only a few hours old. I’ll send pic

 

[POPPS]

Like in a car,,,in the throttle body...you can buy mass air flow sensor cleaner,,,and the problem is fixed,,,could be dirty throttle body,?,,,I doubt its the tps...

 

[Jmperry1018]

If it’s rich can I diagnose with my cando pro?

 

[POPPS]

Wow...nice,,,Man...I don't know,,,but others on here will chime in eventually...do you have any error codes??

 

[Jmperry1018]

Yea got the code reader day one of the twin gti se skis I acquired last fall.

 

[Jmperry1018]

I also no that not every thing will throw a code

 

[POPPS]

Appears there are many sensors,,,you want to tryout the 4-tec forum for help.

 

[dcm0123]

You need to find a way to get the codes. This may tell you what you need to know. If you are having problems connecting the scanner to your computer, the company which makes the scanner was very helpful to me or ask here.

 

[Jmperry1018]

So far I agree it’s running a bit rich and I’ve gone over the sensors with cando pro on the laptop. Very cool by the way. As well as bench checked

 

[dcm0123]

No stored codes?
If you find them, write them down then clear them and see what comes back.

If "all" plugs are burning black, it is doubtful the problem is related to the plug or coils.

I would check all temperature sensor connections. Depending on your year there may be one in the cylinder head (water), one in the intake manifold (air temp) and one in the exhaust. A poor connection could cause the computer to think the temperature is lower than it is and feed more gas into the engine than it should. My recollection is Candoo will tell you the temperature but not necessarily it is out of range.

I would also check the MAP sensor. Not sure how to do it. It controls spark advance and fuel as well. I did see one link which stated try unplugging and running.

Is there a Super Charger and if so, is it working properly? Insufficient air can cause a rich burn. Anything stuck in the air intake ducts like an animal nest?

 

[Jmperry1018]

ive had a bit of fun and frustration here chasing down all the gremlins. 2007 gti se still running rich.

 

[Jmperry1018]

ive had a bit of fun and frustration here chasing down all the gremlins. 2007 gti se still running rich.

so i unplugged that map sensor and it threw a code i started it anyway and she wanted to run better than ever a little too well so i shut it down quickly

 

[dcm0123]

When I had to replace the Super Charger inter-cooler on my 2005 RXT, I read if water comes in contact with the MAP sensing element, the sensors go bad.

Do these machines have water cooled super chargers? If so, this could be the source of the water.

If you decide to replace the MAP sensor and there is a seal around it, I suggest you buy the seal as well. For electrical components I would only buy OEM.

 

[Poormanracing]

If the map sensor has seen any water they go bad and I'm pretty sure if the sensor is green they where updated.

 

[Jmperry1018]

Does it always have to be the last sensor you evaluate spent hours testing everything else