I'm seriously ticked off (exhaust)!!??

[viperkd77]

Ok, i had slight mods to my dsm before i had an exhaust put on this september. I ahve a 97 gsx auto. I had an intake and mbc, thats about it. I was set at about 14psi. I was running well, gettin like 19mpg in town and 23-25mpg highway. I have a 3inch no cat exhaust put on. Megan dp with custom piping with megan muffler. Straight back, no cat. To get the old exhaust off it was a pain. The rear 02 was a pain to get out,etc. Either way, put the new exhaust on, real tight fit, sturdy though and it seems there are no leaks. It sounded decent pullin away from the garage, It seemed the car was tryin to get used to it, sluggish shifts, etc. Now my mpg is like 10-12mpg. NOt really much black smoke at first, but not it is awfully black. During this problem, i purchased dsmlink and a 1g tb. Test for boost leaks, none. Dsmlink showed good voltage on the 02. Also, i have no cel's from cat removal. The car seems to run and sound worse everytime i drive it. Granted it is an auto, my shifting is awful, the car runs and idles at higher rpms. Honestly, its slower. I dont know what is going on. I acutally bought a new front 02 and am trying to install it now. Could be $100 waste??! Somebody with some real knowledge, please help me. I cant afford to have the dsm sittin around and im serisouly jsut fed up with this car right now. thanks.

 

[viperkd77]

also, the last time i drove it, the throttle postion and tps volts on dsmlinbk have no readings. I is blurred. Before, i could read both, could this 2g tb be bad now as well? Also, since this, black smoke all the time. My muffler sounds even worse, like a farm tracker, it cracks, etc.

 

[92awddsm]

You have to switch the plug wires around when using a 95 eprom in a 97-99. You also need to select cas invesion on the link. Have you done these things?

Taken from dsmlink website:
For the 2G guys, the '95-'96 style Cam Angle Sensor (CAS) sends out a signal that's electrically "inverted" from other DSM cam sensors (1G or '97+ style). When you put a '95 ECU into a car with a non-95 CAS, the ECU ends up swapping the firing order of the injectors. In most cases, this produces very little noticeable difference in drive quality. But we offer the option to invert the CAS signal anyway just in case. You can selectively invert this signal with the DSMLink software as you wish. You will still need to swap your spark wires, though. We can't control spark firing order in the EPROM at crank time. So even with CAS inversion, you still have to swap plug wire 1 with 2 and 3 with 4.

 

[viperkd77]

yea, i did that. this gas problem and slow sluggishness started before i even got dsmlink or a 1g tb. it simply happened after putting on the exhaust. It has to do with how i put it on or the sensors or soemthing..???

 

[sawnuoff]

were there any grounds hooked to the exhaust for o2 s? i have herd something about that before, and there was a ground strap hooked to mine before the swap i just made another to replace that one.

 

[95gs200k]

are you running excesively rich? It neaarly sounds like your car since the install has a better flowing exaughst and is adding more fuel. I would try to retune it. It is necesary after any mod is done to a veicle to retune the car. simple boltons (or offs such as a cat) can have a drastic effect on a car especially a turbo when dealing with exaughst or intake modifications.

 

[viperkd77]

there was a ground near the rear 02. i forget exactly how it was connected, but it was very worn.. i figured it was worthless, could be wrong

 

[playitlouddsm]

Hook that ground back up. Some say it doesn't do anything but others think its worth while. Its easy to hook up and could possibly be a simple fix.

 

[playitlouddsm]

Oh yeah if the new exhaust doesn't have any spot on the pipe to ground it to. Just use a worm clamp to hold it to the exhaust and bolt the other end to the stock location.

 

[viperkd77]

Sounds like an idea. Next time im home from school i try to get to it. By the way, got the new 02 in with some fidgeting. Havent had a chance to drive it yet though.

 

[fp-green-95tsi]

Did you swap your 2g tps onto the 1g throttle body when you changed it?

 

[EclipseTrbo420A]

Whats your link chip burned for, injector wise.....and whhat injectors you running.

This is a stupid problem to have for so long. The exhaust would not cause it.

 

[viperkd77]

hey, yes i put the 2g tps on thw 1g tb. Programmed for 550 and running 550. Remember, this problem all happened before i even got the 1g tb and dsmlink. But yea, now i get no tps on link and i did before. Also, how can i l,ook at fuel trims on the link or use it to help figure out wut is goin on?

 

[viperkd77]

Ive driven the car now, i really see no difference between the old and new front o2 sensor. Really dissapointed at my waste of money. Ne1 have any ideas about maybe doing something to the rear sensor. I have no cel from no cat. I was told to try jsut disconnecting the rear 02 and using my dsmlink to delete the cel. ???

 

[bushy]

The rear o2 sensor does NOT do anything to affect engine performance.

And the reason you have no cel is because dsmlink will automatically ignore the rear o2 sensor.

 

[redeclipse7782]

Why dont you post a dsmlink log????

 

[bushy]

Why dont you post a dsmlink log????

Yes I was just going to ask that.

 

[viperkd77]

how do i take a saved log and post it??

 

[bushy]

you have to go into the c:\program files\dsmlink\runs and find the log that you saved. Transfer it from your laptop to your desktop then add it as an attachment on here.

 

[viperkd77]

here is one with new fron 02 sensor, dont think it was the problem, really didnt change much.

 

[elfroggo]

Your front o2 is cycling so that looks fine. Your airflow overall is super low. It looks like you might as well not be turbo. Are you giving it gas at all?

Do you hear your bov releasing air at all when you let off shifts?

And if you're getting 10-12mpg and feels sluggish your fuel must be going somewhere. Probably running super rich.

 

[chicagoavenger]

Is your maf going out?

 

[BISHILVR]

Are you sure that your auto transmission is'nt stuck in limp mode? (2nd or 3rd gear start)

 

[viperkd77]

if u look at the log, you can tell when im flooring it and when im coastin. i was goin down the freeway. I was thinking maybe it had something to do with the maf, i dunno. Also, my auto tranny has shifted wierd since the exhaust installation. It cruises at much higher rpms, shifts awkward, etc. I dunno if that IS the problem or something else is simply causing it to shift awkwardly. If someone needs more logs i ahve a few saved. let me know. thanks

 

[BISHILVR]

I would really suspect the tranny at this point. Been there done that.