gaedbo

Hi, I'm hoping that my Data Log can be read. The outside temp was 85 degrees, with humidity at 34% and the barometer at 29.99 in Saint Paul, MN.
The ASR was ON while I accelerated to the 5000 RPM from a rolling start. I turned the ASR OFF a couple of minutes later. I appreciate your input.

Injuneer

I'll try downloading it tomorrow.

Injuneer

Downloaded, set up in Excel. A bit difficult to review because there are a lot of data faults throughout the log. Thinks like a line row of impossible values for various functions, and 1 to 3 DTC's set. Data errors can be due to interference on the signal line from nearby high voltage wires.

There is a flag to indicate when ASR is active, and it was not active during that acceleration pull. The only time it was active was when the engine was warming up, for less than 1 second, at engine run time 68 seconds.

Is there a particular problem you are having with the way the engine runs? Or are you just looking for confirmation that everything is OK? Fuel trims look good. Sensors seem to read normally. There is some knock retard that I need to look at more closely.

I'll need some more time to look it over.

gaedbo

Thanks for looking at it Fred. Yeah, basically I was wanting to confirm everything was the way it is supposed to be. I for sure didn't turn the ASR Off until after the Acceleration Run. When I pressed the toggle switch to turn it Off, the indicator on the dash board lit up to tell me I had turned it Off, otherwise I usually drive with it On. Do you think I should investigate further. If it is Off, (But doesn't indicate on the dashboard) and doesn't effect or hurt anything else, I guess I'm OK with it being Off.

I appreciate any and all input you are able to give me. Do you think I should do another Data Log, but drive a different route ? If you don't think it has something to do with the car causing the weird results then I won't get to worried about it then.

I did notice while I was driving, that I would see a red blip once in a while on the far right of the display but I couldn't focus on it while driving to see exactly where it was coming from.

Injuneer

I have no experience with ASR. My initial reaction was that someone had installed the aftermarket module that reverses the function of the ASR button, changing it from on by default when the engine is started to off when the engine is started.

The "interference" on the data line is not from external sources. It's from the high voltage in the ignition system. See it a lot.

gaedbo

Is that something I should be concerned about ? If so, what would I need to do to correct it. Would the High Voltage be the spark plug wires and the connection from the Coil to the Distributor ?

Injuneer

It's not a problem with the way the engine runs. It just interferes with analyzing the data. Maybe Gary can comment on possible sources of interference. It isn't unusual, see it a lot. Datamaster used to have a write up in their manual explains the possible sources, but when I tried to go to the TTS Datamaster download page, I got a warning that there was a risk of malicious downloads on the site, so I aborted.

gaedbo

Ok Fred, thanks for all of your input. This site with yours and Gary's, and the other Moderators knowledge and input is awesome. You site has saved, and helped me and many others so much. Thanks for all you do.

Injuneer

Thanks for the positive feedback.

GaryDoug

One possible source of interference is a marginal alternator. Either a shorting or open diode or worn slip ring brushes can create a lot of electrical "noise" on the 12v power bus. Usually you need an oscilloscope to see it.

gaedbo

Thanks for the input Gary. I don't know of anyone with access to the ocilliiscope, so I guess for now I will just let it be as long as the car seems to run as well as it does.

Also, thanks for the Scan94/95 software. I really liked watching and experimenting with the controls during replays of the Scan. I feel I was learning something with all the catagories of data to view and evaluate. Watching temperatures, rpms, etc as they varied.

Injuneer

Still looking at it. Got sidetracked over the weekend.

Injuneer

Most things look OK. Fuel trims are all within +/- 5%, and well balanced side-to-side. O2 sensors seem responsive. In PE mode (~WOT) the O2 readings look good. Always risky to use the readings in PE mode, because they can be inaccurate at rich conditions. But yours are consistently in the low 900mv's, and both sides are near identical.

Things that look normal:

-System voltage, mid-13's
-MAP at idle and WOT
-TPS at closed (0.65V) and WOT
-MAF at idle and WOT
-Spark advance
-Goes into closed loop OK, at normal 206-seconds.

Things that are "off":

-Idle air (IAC) is fully closed (0 counts) at idle, but idle is still above target. Make me wonder if there is a vacuum leak somewhere. But with the MAF readings right where they are supposed to be, not sure there's a vacuum leak. At very high engine load, the PCM does add about 4.7% extra fuel. See if the throttle blade is fully closed, or possibly hanging up a bit open. If slightly open, back of slightly on the throttle stop screw until the IAC counts start to rise, to at least 20. TPS volts will drop, but as long as you stay above 0.25 volts, you are OK.

-AIR pump is called for by the PCM at cold start, but I don't see any evidence it's actually running. No code, so there's a good fuse in the circuit. No big deal whether it's ther or not, but if it is there, and it's running, may be a problem with air flow into the manifolds (faulty check valves?)

-Lot's of knock retard in two WOT pulls. Odd though..... starts out with little or no knock retard for the first half of the pull. All of a sudden in one pull the knock counts increase a bit, and for the second half of the pull here is constant knock retard in the range of 4 - 10-degrees, before it starts to decay near the end of the pull. I look at every sensor, every status flag, whatever, and canno find a single bit of difference between the beginning of the pull with no knock retard, and the end of the pull with a lot. EVAP purge is active at all times, so that is not a sudden cause of a lean condition, and the O2 sensor reading averages are virtually identical for both halves of the pull. Is it possible you have something knocking or rattling in the exhaust, or motor mounts?

Really odd. Everything I looked at was "healthy", compared to most of the data logs I see, but then the knock retard shows up. I can't explain it with the data log.

gaedbo

Wow, thanks for taking the time to evaluate in such depth. As far as the Air Pump goes, I had removed that last year and plugged the opening in the exhaust manifolds, and all other connection points. I will check out the IAC like you suggested. I cleaned the Throttle Body last year and put new gaskets in. I have checked for vacuum leaks before, but will do it again. I am pretty sure my throttle blade closes all the way, but will re-check to make sure something may be preventing it from operating correctly. When I did the WOT, as soon as it reached the 5000 RPM I slowly backed off on the throttle if you think that might be related to the knock retard issue. I don't believe I have rattling in the exhaust, or a motor mount issue, but will check those items also to make sure. Your input is awesome, thanks so much.

GaryDoug

You might want to check the condition of the wire and connector on the knock sensor (side of block ahead of starter). I suppose it could be loose and making intermittent contact when the engine rpm is high. Or the wire could be touching the header when the speed is enough to blow it around.