yorkfitter

I have been trying to figure out if my engine is rich. I have a black dust on the rear of the car after driving it and the tips are always needing to be cleaned. I have put a heated sensor oxygen sensor and it has improved, but my car stinks. I have no emissions and no cats and the engine was built and tuned by TPIS. I doubt TPIS made a mistake with the tune, Is a wide band o2 sensor worth the money. Is it possible for the car to be running rich even if the oxygen sensor connected to the ECM is saying everything is OK? Also, does anyone have any option on this one. http://www.ebay.com/itm/400343610177

Cliff Harris

Data log and check the BLMs. If they are at and near 108 then you're rich. If your O2 sensor cross counts are not increasing constantly at one count every 1 to 2 seconds then you have a problem.

A wideband O2 sensor tells you what the AFR is at this particular instant. They are mostly useful when the ECM is in open loop mode (WOT, for example).

tunedport85inject

here some screenshot from a datalog session of my 85,she's running really rich,like your car.investigating about it,never been so rich,never so much at least.She's idling very rich,never went over 110 blms,from tunerpro rt various rpm range,closed loop,operating temperature:
[IMG][/IMG]
[IMG][/IMG]
[IMG][/IMG]

but my wideband lc-1 says 14.7

[IMG][/IMG]

FrankieD

Looking at this datalog screen, something does not make sense. Your BLM is at 108 yet the O2 is reading 266.40. With that O2 value it should be running very lean actually. Are you using the stock factory O2 for this reading? where is your wideband mounted? Could be that you either have an exhaust leak or cam reversion happening. Further setup details would help troubleshoot.

MikeT 90 C4sixer

That sure is a good WB to start with. I have an older LM1 in my IROC Camaro, and it has been very useful. But do what Cliff says above, get some scan data and see what your numbers are first. You dont really need the WB to get the basic tune to come in. You could have some bad injectors, or an O2 sensor.

yorkfitter

Doeas anything look abnormal here?

MikeT 90 C4sixer

I would say no, nothing unusual. I would like to see your O2 sensor voltage, the crosscounts, and the LT counts on the graph. That would give you a good baseline starting point to see how your tune really is.

MrWillys

Mike, my understanding of the o2 is it already reads the E10 mixture lean and uses the learn function to compensate. Or, if you were to log E10 vs straight gas the E10 would just show a slightly higher blm well within the parameters of the ecm. With E85 just add about 35% larger injector. So id flowrate is set at 30 lbs with an installed injector being 42 the O2 without knowing will adjust to a gasoline 14.7 but really be about 9.7.

If this doesn't make sense read this:

http://ls1tech.com/forums/fueling-in...r-ls1-e85.html

MikeT 90 C4sixer

Mr. ******, where in my post did i say anything about tuning for E10 or E85? the OP indicated he was running rich. he didnt say what fuel he is running. later he posted a picture of some DM data. i just asked that he change his graph to show how it really is running. remember, our TPI cars were designed in the early 80s. I doubt they were designed to run on any ethanol. if your tune is totally stock, and you run E10, it will be off, but you may not notice it. ethanol does bad things besides make your tune off a little.

MrWillys

First, no offense was intended. I screwed up and meant this response to be in the WOT afr thread where you did mention E10. My mistake. Honestly, I thought you would enjoy reading about its correlation with the o2?

MikeT 90 C4sixer

Understood. i wondered if maybe your reply was for another post. I only glanced at the article on ethanol fuel. Not really interested in E85 myself. But you can never learn too much in this game!

yorkfitter

just got the car dynoed the number are low compared the engine even with driveline loss, and input would be appreciated. motor is 495hp@5900rpm
472tq@5200

yorkfitter

Here is a picture

FrankieD

You are running way too lean for WOT from 3300 to 5500 rpm. Need to richen it up to about 12.8 AFR