Stalling issues after mods

[91TSi FWD]

So here's my delema. Once the car gets to its operating temperature, whenever I push the clutch in, the engine just drops to 0rpm & dies, and if it doesn't die, it's struggling to keep idle. It all started after I did a lot of work to the car- 2G mas, new IC piping/intercooler, intake pipe, SAFC, 650 injectors, fpr, EVO III 16G, Type RS BOV(recirculated), Blitz Dual SBC, etc. It will only stall once its in operating temp. The stalling started after the mods were done, it ran like new before.

Even when I was dyno'ing my car to tune it, it was stalling on the dyno. Other than that the dyno went well, couldn't find anything wrong with the fuel curve.

All the belts are tight, plugs are brand new, plug wires are fine, I double checked my ECU, no leaky capacitors, all wires for the SAFC hooked up properly, my throttle body is very clean, fuel flow @ idle is fine & no boost leaks. The only parts I can think of that may be bad are the 2G MAS, cam sensor, or my ECU is just pooched. Also, my battery is always low, I leave it sit for a long time between uses with the alarm on & usualy have to charge it before use, and I don't drive enough to get a good charge.

I've tried the obviouse of just playing with the base idle set screw, but does nothing to help the stalling.

If anyone has any ideas or has run into this kind of problem, any help would be appriciated. its a 5-speed TSi FWD.

Thanks for any and all help.

If this should be in the noob forum, feel free to move it.

 

[dub2gsx]

My first impression was the O2 sensor but you said your fuel trims looked fine on the dyno and you wouldn't be able to tune with that out. So the next thing to check is the alternator or the ISC. My guess is the ISC because my friends did the same thing on his 1g for a while. But my car did what you said your car is because of the fuel trims being too lean at idle. Then another time was when my alternator was about to go out.

Try those, hope that helps...

Brian

 

[oldman]

1. At the very least you have FPR overrun which can either cause or contribute to your problem.

2. How do you know you have no boost leaks? What were the final conditions of your boost leak test?

3. What are the adjustments on your SAFC?

4. Have you tested the alternator which can account for both low charge and stalling?

 

[91TSi FWD]

My first impression was the O2 sensor but you said your fuel trims looked fine on the dyno and you wouldn't be able to tune with that out. So the next thing to check is the alternator or the ISC. My guess is the ISC because my friends did the same thing on his 1g for a while. But my car did what you said your car is because of the fuel trims being too lean at idle. Then another time was when my alternator was about to go out.

Try those, hope that helps...

Brian

My 02 Sensor is brand new, havn't checked the ISC though, may be something to look at replacing, also the alternator has quite a few miles on it, So I'll try that as well, I'm sure I can find a used one cheap.

 

[91TSi FWD]

1. At the very least you have FPR overrun which can either cause or contribute to your problem.

2. How do you know you have no boost leaks? What were the final conditions of your boost leak test?

3. What are the adjustments on your SAFC?

4. Have you tested the alternator which can account for both low charge and stalling?

Per your questions on 1, 2, and 3, I had my car professionaly tuned on the dyno, they set the SAFC from idle to WOT. SAFC settings will be a bit different for every car & setup. The FPR is not being overrun, this was also adjusted on the dyno.

For the intercooler pipes, after the dyno I was frustrated because of the stalling, this was one of the first things I did. I took it to a local tuning shop & they did a compression test, leak-down test & boost leak test. Before all of this I changed the spark plugs & wires as well. They advised me their were no problems with any of the diagnostics that they ran.

I'll check the voltage on the alternator when I get a chance.

Thanks for the help,

Matt

 

[oldman]

Matt, if these are the same guys who told you you have no fpr overrun, I would go back and double check everything they've done including the boost leak test and the tune itself. The B&M fpr modifier, keyword being modifier, is not a true adjustable fpr, it modifieds the stock fpr so you can increase fuel pressure on the stocker which does nothing for fpr overrun. For a 255 not to overrun the B&M, you would have to have fuel leaks, defective pump/install or clogged fuel filter. Either these guys are not being straight with you or they're clueless.

 

[91TSi FWD]

Matt, if these are the same guys who told you you have no fpr overrun, I would go back and double check everything they've done including the boost leak test and the tune itself. The B&M fpr modifier, keyword being modifier, is not a true adjustable fpr, it modifieds the stock fpr so you can increase fuel pressure on the stocker which does nothing for fpr overrun. For a 255 not to overrun the B&M, you would have to have fuel leaks, defective pump/install or clogged fuel filter. Either these guys are not being straight with you or they're clueless.

Just one thing to note, which I appoligize and should have cleared on my first post, is that my Walbr 255 pump is sitting in my shed right now. I've owned it for 3 years, but havn't had the time to install it. Its a big job to re-wire the whole system, and with my career, I just can't get time. So when I dyno'd the car, it was, and still is, on the stock fuel pump. I do regret buying the B&M, should have done it right the first time and bought a fully adjustable regulator, I rarely skimp on things like that.

The stock pump still did its job of obtaining 317whp, but started to lean out on the top end, and yes, started to knock at high RPM's(6800+) so I don't plan on running it hard until I get the 255 in. The fuel curve was tuned very well up to about 6500RPM.

Also, the fuel filter is 4 years old, but I've only put about 12,000km's on it since then, so it should be very clean still.

I'll update my mods list tonight.

Thanks again for the help.

 

[oldman]

That's a different story than, still doen't mean the issue is not the tune. Do you have logging capacity or are you one of those tune it and forget type of guy?

 

[91TSi FWD]

That's a different story than, still doen't mean the issue is not the tune. Do you have logging capacity or are you one of those tune it and forget type of guy?

haha, definatly not. I just have a datalogger right now. I would like to get a DSM link, but the price of them is just too much right now. I've only put on about 150km's since I dyno'd the car(I rarely drive it). The only thing I've done is play with the biss, and the SAFC low-throttle settings from 0-4000RPM to try and deter the stalling, but nothing has worked, so I set everything back to my readings right after the dyno.

I'm not saying that its not the tune, it could very well be. When I first did all the mods is when it started being a pain, after the dyno tune, it was the exact same.

I'm still leaning towards the 2G MAS. When I bought it, the guy said it wasn't from a 2G DSM, but from a different car which gives the same readings & has the exact same plug. I used this site to install the MAS- http://www.vfaq.com/mods/2GMAF-1G.html

Do any other cars use the same type MAS as the 2G, but may read a bit different? This is the best pic I have of my MAS right now, but its an old pic, the manual boost controller is no longer their, amoungst a couple other small changes.

http://www.nacdsm.org/gallery/v/Matts-Galery/album50/Car-almost+done+003.jpg.html

 

[oldman]

Feel free to tell us everything at once now. I need a better picture of the mas to tell you for sure. Does it look like the picture in the vfaq? Are all your honeycombs intact? I also strongly suggest performing a boost/vacuum leak test, recheck your ignition base timing, make sure through the logger that the ISC/TPS are functioning and in proper range.

 

[Ultimatedsm]

Can you log your run? With my DSMLINK, I can check the MAS signal to see if it isn't going crazy. When your car is running disconnect your MASS AIR and let us know if it still idles the same or if it idles better with it disconnected etc.

 

[91TSi FWD]

Feel free to tell us everything at once now. I need a better picture of the mas to tell you for sure. Does it look like the picture in the vfaq? Are all your honeycombs intact? I also strongly suggest performing a boost/vacuum leak test, recheck your ignition base timing, make sure through the logger that the ISC/TPS are functioning and in proper range.

The MAS looks exactly like the one on vfaq. Maybe I'll grab the number off it & take it to the chrysler/mitsu dealership and see what its from. All honeycombs are intact & undamaged. I just grabbed my logger to go test it quick, and the batteries are dead Yeah, that's how much I drive my Talon. When the batteries died, I lost my software.

I just emailed digital tuning to get another copy of the logger software, so hopefully I don't have to go through too many loops to get the software. Like I said, I don't drive the car often, but it would be nice to get this straightened out.