Running wayy too rich now

[Turbo 420a]

Ever since I put on the 310cc injectors my car has been running very well and completely driveable. It was obviously running a little too rich, but nothing that stopped the car from operating like it should. However, as I was driving it into town yesterday it started acting very funny in first gear. Taking off in 1st gear my car would slug forward and very SLOWLY climb rpm's from 1k until my turbo spooled, which then the power would hook back on and everything was fine. I stopped the car again and this time held my rev's @ 2.5k (when boost begins) and took off in 1st gear, and despite squeeling the tires, it did set into motion just fine. This started to happen frequently in 1st gear.

I started my car up this morning and it sounded like my car's idle was very unhealthy and MUCH richer than before. I let my car warm up. Once it did I played with the rpms a little bit, sometimes it would have a little trouble climbing revs and then sometimes it would rev like normal.
While at idle my vacuum gauge was reading around 10, different from the old idle vacuum of 18. I turned the Clipse' off, stepped out and my whole garage reaked of unburned fuel and all of the dark smoke was making my eyes water. Looking at my muffler I could see that it had a fresh coating of black residue built inside of it. I guess this means it is time for that AFC?

Just wondering if anybody has an idea as to why I was able to drive my car with the 310cc's for more than a thousand miles without a problem; then one day I start it up, with not a single thing changed, and it runs wayyyy differently... I will be ordering the S-AFC tomorow, hope that fixes my problem

 

[siueclipse]

I too am running very rich. You can call hahn and get some reducers. They are only $1. Put them in your fuel line where it hooks up to the fuel pressure regulator. Make sure you are running like 25 or lower psi of base fuel pressure as well. Im running 21psi of base fuel pressure and am still rich.

 

[98Turbbo420A]

I'd personally get an S-FMU from Greddy and a fuel pressure guage! An AFC isn't a good idea with out cars because it tends to advance timing, and if you're not use to using it, the S-FMU will work fine!

 

[Turbo 420a]

Are you using the S-FMU 98turbo? Is there anything it can't do that the S-AFC can do a lot better?

 

[98Turbbo420A]

The S-FMU is mechanical, it controls static FP, Idle FB and WOT fuel pressure plus it has a rate of rise disk that you can choose for your application. I tend to stay away from electronics unless I don't have a choice! The S-AFC tends to advance timing in our cars for some reason, and as we all know that's bad if you run a decent amout of boost!

 

[fast1.8sohcDSM]

That is the sweet thing with the 1.8 having a distributor, none of that DIS worries about the AFC. Although my S-AFCII is reading that my RPM gauge is lying.

 

[allwheelTSI]

i agree with the othersgetting some sort of fuel management is going to be best,reducing fuel flow to the rail is gonna result in the same amount of fuel for the most part,the ECU controls how much goes in,not the fuel line.

 

[Turbo 420a]

My mechanic said that quite possibly either the stock fuel pressure regulator or my FMU (doubtful) failed and that's the reason my car was running fine before - and now suddenly not. Anyone ever heard of, or know the results of a failed stock FPR?

I highly doubt the Vortech FMU is busted as it doesn't control fuel pressure until boost comes online; plus it's at idle my engine sounds most unhealthy. Kind of like it's rumbling on two cylinders.

 

[dudasd]

Originally posted by Turbo 420a
Ever since I put on the 310cc injectors my car has been running very well and completely driveable. It was obviously running a little too rich, but nothing that stopped the car from operating like it should. However, as I was driving it into town yesterday it started acting very funny in first gear. Taking off in 1st gear my car would slug forward and very SLOWLY climb rpm's from 1k until my turbo spooled, which then the power would hook back on and everything was fine. I stopped the car again and this time held my rev's @ 2.5k (when boost begins) and took off in 1st gear, and despite squeeling the tires, it did set into motion just fine. This started to happen frequently in 1st gear.

I started my car up this morning and it sounded like my car's idle was very unhealthy and MUCH richer than before. I let my car warm up. Once it did I played with the rpms a little bit, sometimes it would have a little trouble climbing revs and then sometimes it would rev like normal.
While at idle my vacuum gauge was reading around 10, different from the old idle vacuum of 18. I turned the Clipse' off, stepped out and my whole garage reaked of unburned fuel and all of the dark smoke was making my eyes water. Looking at my muffler I could see that it had a fresh coating of black residue built inside of it. I guess this means it is time for that AFC?

Just wondering if anybody has an idea as to why I was able to drive my car with the 310cc's for more than a thousand miles without a problem; then one day I start it up, with not a single thing changed, and it runs wayyyy differently... I will be ordering the S-AFC tomorow, hope that fixes my problem

While at idle my vacuum gauge was reading around 10, different from the old idle vacuum of 18.

I think everyone overlooked a more serious issue than fuel pressures. Bro, from how you say your car sounds at idle, and by the way your vacuum gauge is reading I think you need to do 2 things.
1. Pull your dipstick and see if you have air or puffs of smoke coming out of it.
2. Do a compression check.

The reason you can be running so $hitty might just be due to the inevitable cracked ring lands that go so well with boost and stock internals. Mine is acting and sounding the same way as yours and it is due to that very problem. And if that is the case on yours, welcome to the club and make sure to post pics of the cranage when you tear it apart.

 

[Turbo 420a]

Originally posted by dudasd
While at idle my vacuum gauge was reading around 10, different from the old idle vacuum of 18.

I think everyone overlooked a more serious issue than fuel pressures. Bro, from how you say your car sounds at idle, and by the way your vacuum gauge is reading I think you need to do 2 things.
1. Pull your dipstick and see if you have air or puffs of smoke coming out of it.
2. Do a compression check.

The reason you can be running so $hitty might just be due to the inevitable cracked ring lands that go so well with boost and stock internals. Mine is acting and sounding the same way as yours and it is due to that very problem. And if that is the case on yours, welcome to the club and make sure to post pics of the cranage when you tear it apart.

I let my engine warm up this morning and proceeded to an empty road nearby to find out anything else about the problem. Well, the first few pulls I had the same flat spot problems. Then my car started to act normal as I drove it more. Once the motor is fully warmed up this problem will become close to non-existant. This wouldn't be the case with cracked ring lands, that problem would make the symptoms always apparant, correct?

I thought I would put in some new NGK's tonight, just to be safe it's not ignition related.

 

[Kirby]

Get a data logger and check your fuel trims, that will tell you what is going on. You should be fine with just the sfmu, you prolly won't need the SAFC. The reason the SAFC advances timing in our cars is because it cuts map sensor voltage. I don't think the problem of the rings would change if you started out at a higher RPM either. It sounds like fuel trims to me, are you just using the regular fmu? what disk are you using in it?

 

[Turbo 420a]

Seems like these big problems always turn out to be something basic. My spark plugs were one of the reasons for this problem. When removing the old spark plugs I noticed how burnt they were; car ran great after that change. Of course I'm still running rich like before, just can't quite decide between the S-FMU or the AFC... I am not going to be boosting above 9psi anytime soon - and if I ever do go beyond that (internals) I will have an AEM engine management system to go with that. So is the S-AFC, when used at sub-9psi boost a great threat to our engine? Does anybody know which is better in terms of 'ease of tuning'? The S-AFC wiring isn't a big deal for me. I'm just concerned as to which is more exhaustive to tune with. I will have to complete the install/tuning in a single day so I can go to school the next.

Kirby, I don't know what the current disk on my FMU is. I would guess it is the same one you have, that came with our kit. What components are you using on your fuel system?