My car is a '98 A4 with around 60K on the clock. the only other mods i have that aren't in the sig are port/polished T/B and MAF sensor and an HSW 125 dry shot. I ran my car at the track yesterday on the 125 shot with bottle pressure at 950 and it did pretty good the first two runs but after finishing the third pass it statred to run like it was misfiring, running like i just disconnected one of the plug cables. I'm guessing i fried one of the plugs (TR6 gapped at .035) but i wanted to get som more expert opinions. i pulled the first two plugs on the driver side already and they werent carbon fouled or anything like that but the ground strap did have a slight green tint to it, which i have been told isn't anyhting to worry about. i'm gonna pull the rest of the plugs tonight but i wanted to know if there is anything else i should be on the lookout for while i'm down there...

 

My first advice would have been to pull all the plugs and check em. Had the same problems on my friend's car, and the #7 plug was burnt....

Also check your coolant and make sure theres no oil in it and vice versa...

-Will

 

Do what Will said above first. What was the injector duty cycle at on the 125 shot?

Thanks,
Matt

 

don't have a Tuner Suite yet, i know shame on me, smack me up side the head so i can't tell you the duty cycle. don't worry i'm am gonna try an get it here soon. Anyways do you guys know where i can find a chart the has the cylinders numbered, i don't know which cylinders are which. Checked my oil level yesterday and it was where it chould be with no coolant in it so the head gaskets should be fine.

 

Did you check airfuel before spraying? Since you have a cam you may have been out of injector as well.

The passenger side is all even. Sarting from the front 2,4,6,8
The drivers side is al odd. Starting from the front 1,3,5,7

Dave

 

pulled all the drivers side plugs just awhile ago. first pic is of plug #7


this pic is of all four plugs in from left to right: #1,#3,#5,#7. as you can see they get worse as you move further towards the back of the motor. What can you guys tell me by looking at these plugs?

 

bigger pics...

 

Getting too hot on that cylinder (its usually cylinder 7, hence the need for the crossover tube). This is the reason the ground strap has melted to touching the diode. You REALLY need to get some software to datalog. You need to check your injector duty cycle, you need to know your A/F, you also need to be able to monitor your knock sensors and make sure you're not detonating. I'd leave the kit alone until you can get tuning software, or get the car to a tuner....look on the bright sie though, it coulda been worse

-Will

 

Yeah everything he said. You really don't wanna run the nitrous till it gets tuned!!! But you got damn lucky it looks like.

 

Gotcha, the bottle is not even in my car right now. i'm going to change my oil and the other 4 plugs within these next few days. the car runs fine now that i have that #7 plug changed. I'm going to check it when i get home today. i'm no expert but to me it looks like that #7 plug is oil fouled (black and shiny). do you think i would be burning oil in that cylinder and if so why? BTW thanks for the replies!

 

It's wet because it couldn't fire any longer. Hence the dead cylinder. The only way to "read" a plug is under the condition you need to read. ie: wot, then cut the n2o and then cut motor. Coast to the side and pull the plug. Once you let it run, you're only checking that condition.

 

Alright, so i shouldn't have to worry about burning any oil in that cylinder then right? is all the black build up from unburnt fuel? from what i've read up on i have learned that the #7 cylinder runs the leanest, then #8, so #8 plug might look similar to #7??? what do you guys know about the TR6's turning green on the ground strap? i've been told this is a good thing...

BTW what is a crossover tube?

 

Bump, Bump...

 

another word of advice.... dont port your stock maf... and dont remove the screen. If you are running a dry kit.. you want the maf to remain stock and spray the correct way thru the maf.

 

hmmm, i've been told different about the MAF, not to point fingers but i remember reading on of Robert56's post stating you should remove the screen because if you are spraying the directly at the MAF you will freeze the screen, is this right?

 

news to me... .only one way to tell.... take the maf off... and hit it with the end of the nitrous line. if it freezes... remove the screen.. but dont port it!

 

whats the reason for not porting the MAF?? Are there people out there running N2O with the thunder racing MAF ends? i ask cause this would pretty much make it a ported MAF.

 

bump bump, dust dust. sorry to bring it back up by could porting the MAF hurt the motor while on N2O?

 

There's been several discussions on porting / descreening. In the end, no real gains from porting it unless you do the cam/heads/intake yada yada.
As for descreening, yes, pretty much everyone rips it out. It doesn't run any different in N/A and works great in N2o.

 

Always remove the screen when spraying a dry hit. the reason being, the very cold nitrous on a humid day will cause condensation to form on the screen IE: big restrictions and inaccurate readings. this could lead to a plethora of issues.
Standard procedure for dry set-ups.
Robert