Our Community is 940,000 Strong. Join Us.


Need Help


navyboy85
07-09-2008, 07:32 PM
So i got a 96 gst and driving it home it spools up real nice but when i get on it a little the fuel/air meter shots to rich and the engine feels like its bogging out how can i fix the problum he told me it needs tuned so what should i do and how should i do it.

Thor06
07-09-2008, 08:34 PM
First off, is the guage a wideband or narrow band o2 sensor? If its a narrow band, I wouldnt take a lot of stock in it.

Secondly, what are you using for fuel adjustment? You cant simply toss in bigger injectors and exect the ECU to know, so you are going to be running quite rich. There's a few ways you can go about it, but for the newbie the best two options would be DSMlink or a SAFC variant + datatlogger.

The SAFC and datalogger is cheaper, but far more limited. The SAFC can only adjust fuel and can only support 650 cc injectors and even then its pushing it.

DSMlink is going to be a little more epensive, but its entirely worth the price. Not only can you datalog and adjust fuel like you can with the above combo, but there is a laundry list of other things you can do such as nitrous controls, no lift to shift, studderbox, antilag, etc. Its about $555 shipped new plus you'd need the EPROM ECU that goes for like $225. You can get the DSMlink and ECU package used for like $600 though if you shop around.

david-b
07-09-2008, 09:05 PM
I vote that Thor gets voted number 1 pusher for DSMLink these days. That's all he talks about in every post. Go Thor!

But dido on what he said about the narrowband. And everything else for that matter.

navyboy85
07-09-2008, 09:06 PM
well there is 550cc injectors and 190lph fuel pump but there nothing controlling it and im not sure if its wide band or narrow how can i tell all i know is theres a meter guage on the side that say lean moderate and rich and as soon as i push it the guage goes to really rich and the car starts to stutter is this bad for the car and could u give me some links for what i need or the name cause im not really sure of what your talking about is it just something for me to use to adjust the mixter so it runs smooth please explain.

david-b
07-09-2008, 09:38 PM
Sounds like a narrowband.
When your driving does it just rock back and forth like a semi-fantastic lights show at a Pink Floyd cover band without the contact high?

Throw it out the window next time your on the expressway and make sure something large and heavy, or a small car with a heavily fat person driving runs over it and buy a wideband. That's the only way you're going to know if you're really running rich or not. You also need something to control the fuel also.

4g63gst20
07-09-2008, 09:39 PM
maybe he is getting comission on every sale. lol

navyboy85
07-09-2008, 09:50 PM
yea it goes back and forth till i hit the gas then goes to read rich so i need to get a wide band whats the diffrence and what should i use to adjust the fuel and air mixer cause it only happens when i get on it and the turbo spools up then when i hit around 4500 rpm it starts to stutter. and slowly climb from there.

steviek
07-09-2008, 10:12 PM
now I agree with everything that everyone else has posted but I just wanted to note that narrowbands are supposed to read rich under wide open throttle. Unfortunately for you there is no knowing how rich is too rich. But I know what I can do !!!
ok stockers are 450s so your uncontrolled 550's make you 18% too rich. Add that in combination with the already very conservative stock dsm tune which is approximately 12-14% too rich and your got yourself one mean rich ass curve. Not to mention the 190 will be overrunning your stock fpr a little bit too but that is less noticeable under WOT. Yes your narrowband is garbage... I had one but gave it away when I realized how useless it was. All it is tapped into your front o2 voltage which goes to the ecu. So essentially all it is doing is measuring the voltage of a narrowband wire. ANd to make things even stupider the voltage is a max of one volt. Talk about a lot of info to be gained from that.

A wideband is its own entity. It removes your factory o2 sensor and sends a 5v signal to the display which converts it to an A:F ratio. THis is what you need to tune. In this "closed loop" system none of the information is going to or coming from the ecu. Therefore if you bypass the o2 then your car is inhibited on its own ability to learn and stabilize the ratio itself. Of course the rear o2 is less valuable then the front so that is the more common one that is removed. You may still receive a check engine light. However, instead of having your car essentially guess whether its too rich or too lean based on a narrowband output to the ecu you will have the ability to take charge with a tuning tool and the wideband enabling you to properly tune the car and eliminate guessing. Naturally the logger is so you don't have to have eyes in 10 places at once and can give you information which you cannot see or hear otherwise. That is why dsmlink is such a powerful tool as it can combine all these factors and enables you to fully control the innerworkings of your car.

Ps link pays me double what thor gets on commisions

Thor06
07-09-2008, 10:24 PM
Ha ha ha, you guys are silly. DSMlink is just a far superior tuning tool, that is unless you are running a track only car and already have a good concept of tuning. For 99% of DSMer's though, DSMlink is the clear answer. I almost dont know how I managed driving a DSM without it. :)

navyboy85
07-10-2008, 05:01 AM
Can i use this to tune the car APEXI SAFC II (http://cgi.ebay.com/APEXI-SAFC-II_W0QQitemZ330251436502QQihZ014QQcategoryZ33598QQ ssPageNameZWDVWQQrdZ1QQcmdZViewItem)http://pics.ebaystatic.com/aw/pics/s.gif</IMG>; and is it alright to drive the car with out the tune till i can buy it or will it hurt the motor.

steviek
07-10-2008, 06:38 AM
Yes on 550's the safc2 will suffice. Thats the exact same tuning/injector/fuelpump combo I had a while back. It got me pretty deep into the 13's. Even without a wideband I can tell you that you need to subtract at least 18% fuel across the board once you get that installed. After that I wouldn't lean it out anymore until you get a wideband

steviek
07-10-2008, 06:39 AM
yes your car will be fine without the tune. Running too rich is not as bad as too lean. the plugs will get fouled thats for sure but the engine is relatively quite safe.

Thor06
07-10-2008, 06:49 AM
Not to mention your fuel economy is going to take a shit dive. I personally wouldnt do it, but I suppose you could if you had to.

steviek
07-10-2008, 11:20 AM
Not to mention your fuel economy is going to take a shit dive. I personally wouldnt do it, but I suppose you could if you had to.

It is already on his car I believe. So I'm sure he knows about his economy

navyboy85
07-10-2008, 06:16 PM
Well guys i was changing out the brakes today and happen to want to look over the exhuast system and guess what there was a nice big hole where it rusted out i think this might have a big portion to why im running so rich what do u guys think about it. From the turbo to the cat is good no holes but after the cat its all messed up, and yes im going threw gas like its water should i still buy afc after i get the exhuast.

steviek
07-10-2008, 07:09 PM
the front o2 sensor which is responsible for telling your ecu whats up is located on your o2 housing which is \FAR prior to where your exhaust leak is. The leak will have no effect on what your sensor is sending to your ecu and therefore has no affect on how your car is running. The rear o2 is for emmisions control and therefore is often why it is bypassed. The exhaust leak is the last of your concerns just enjoy the extra .5hp it is giving you.

steviek
07-10-2008, 07:12 PM
SAFC first then exhaust after. One problem at a time my friend one problem at a time.

navyboy85
07-10-2008, 07:24 PM
Well im just going to do it at the same time to get it out of the way. But doesnt hurt the back pressure having the hole its pretty big.

steviek
07-10-2008, 09:40 PM
bah dude I'm trying to help you here but your questions are getting a little OT. I told you what is causing your richness. Sure fix the exhaust I mean you are going to have to do it anyways but it is not affecting your performance at all in comparison with you driving around at an 8:1 a/f. Simple as that no point in even attempting to make the car faster until you gt that fixed.
All I'm saying is there are probably ten things right now that could be robbing your car of power but it doesn't matter thats for a new thread after you get the OP figured out.

navyboy85
07-11-2008, 05:01 AM
Ok ill tune it first and see what happens thanks for your advice.

Add your comment to this topic!