This is my first foray into ALDL technical diagnostics. In roaming around the Fiero community these last few years, seems like this "yearning for learning" is what motivates a lot of Fiero owners?

OK. I have an 85 Sport Coupe 5 speed, in which I installed a stock Fiero 2.8 V6 after the original Iron Duke sheared an oil pump gear pin on an expressway run! The engine was used from Kick Hill, and I've put 20k on it since installation.

I've spent the last year refurbishing the car's suspension, and was just getting ready to turn some detail attention to the engine. Performance had been deteriorating lately (missing, poor pick-up, etc.).

I decided to start by refurbing the fuel injection, since at installation I had only given the engine a good tune-up. I pulled the Plenum, fuel injectors and manifold and intake runner. I had the injectors professionally serviced by Cruzin Performance, and in the interim cleaned, polished and powder coated the Plenum (and valve covers), cleaned and serviced the throttle body and other components, and cleaned and checked the vacuum lines and connectors. I refurbed the distributor as well (module, pick-up, cap, rotor etc.) and put in fresh plugs etc.

Also from advice by Cruzin, cleaned, derusted and sealed the gas tank, and threw in a new fuel pump for good measure. I installed a pressure guage an the injector manifold, and know I've got good fuel pressure. Reassembled everything.

I first struggled with a high idle, and eventually tracked down a poorly installed hose, but still have a somewhat high idle. I "believe" the car is running rich, and decided to invest in WinALDL with cable and laptop to help me fine tune this thing.

My first data is from 3 runs:

• Car warming up at idle
  
• 55mph 10 mile run
  
• 55mph 2nd 10 mile run
  

I put the data in a spreadsheet and "averaged" all the readings to take a look at what I had:



(Sorry about the over 100k image thing - I'm still learning)

I noticed several anomilies in my data compared to data I've researched in the forum:

• My PROMIDA data = 0! Eveyone else's data shows an output?
  
• My BLM data is a "rock steady" 128, no variation?
  
• My MCU1IO data shows AC enabled (value 1) I have no AC?
  

Using ALDL View, I graphed the 2 55 mph runs. I chose Speed, MAP and BLM for starters since these seemed to be popular overlays for diagnosis:





Notice the rock steady BLM output (yellow line). It remains at a firm 128, no variation?

The MAP graph (green line) seems to jump around a lot, but that may just be me trying to hold a steady 55?

All inputs appreciated folks. I expect this to be a multiple pass project.

Marc in sunny Titusville, FL
85 Sport Coupe with transplant V6
85 GT newly acquired, not on the road yet
84 SE son's car, low mileage, loaded w/options

Try again with Integrator, O2 voltage and closed loop status. Coolant temp is something to watch, make sure engine is getting up to over 195 degrees.

Prom ID of 0 sounds just plain wrong.... You put a 6 cylinder ECM in right? If you pull the cover, what does the Prom read on top?

I can look it up and see what it is for if you tell me what donor was supposed to be and verify application matches.

Map should be a pretty darn steady reading at a steady engine speed/load. That corresponds directly to what you'd see with a vacuum gauge hooked up to manifold vacuum... a good check if you want to verify engine mechanical condition.


It looks kinda like your MAP readings may actually be O2 getting reported incorrectly... .22 to .96 volts would be normal ranging for that. MAP voltage should be around 1-1.5 volt under closed throttle conditions and up around 4.5v when you go wide open throttle... or with the key on and engine off. The number will vary according to engine sealing and altitude.

[This message has been edited by Scott-Wa (edited 10-15-2006).]

quote Originally posted by Scott-Wa: Try again with Integrator, O2 voltage and closed loop status. Coolant temp is something to watch, make sure engine is getting up to over 195 degrees.

Here's a shot with the INT, O2 and CL data:



It gets pretty busy.

For the most part, the actual readings show O2 falling withing the range you suggest. The "average" over 200 readings is .5. Coolant temp holds pretty steady around 168 to 170 after everything's warmed up. I'm not seeing readings for MAP "voltage". The "MAP Sensor" readings range from 28 to 90 from WinALDL, with the "average" being 56 over 200 data points.

The ECM came with the V6 from Kick Hill. He provides the V6 swap as a "kit" including computer, wiring harness, any brackets and cables. I have no reason to suspect the ECM is anything but for a V6?

Marc in sunny Titusville, FL
85 Sport Coupe w/V6 transplant
85 GT - just acquired, not on the road yet
84 SE - son's car, low mileage, loaded w/options

Marc, Are you cleaning out the garbage on your data before you put it into view? Your coming up with some odd looking values, your 02 looks ok on the graph, your int is to high, I`m not sure why your not reaching normal operating temps in the 10 miles runs--the best way to average these logs are to run to normal operating temps, 10-15 mile runs, 55mph (steady) on a strait flat road. If your running any low temp stats, fans, switches, regulators, larger injectors, ect ect , please let us know now--so we are not chasing our tails on this data.. Have you read this post ? https://www.fiero.nl/forum/Forum2/HTML/069590.html
In the photo bucket data, your tps is showning a -2.2 at idle? and the 02 sensor there looks the same no matter whats going on with your engine a 0.5 at idle then through-out both run/logs? Look at the iac counts between runs 1 & 2 , in these your intergrator (int ) & blm look great..
Your blm ==128 is perfect--don`t worry about the a/c enable thing ok?

From 3800superfast's comments:

After this first set of run data I did a couple of things - 1st I verified I was using the correct ECM pick, I was correct. 2nd I put a 195 stat back in the engine (I had a 160 in from some cooling problems I eventually resolved). I did a new data run just idling, and the temps are now fluctuating around 200 - good! However I still note no data for PROMIDA? Does this matter? What is PROMIDA.

I'm going to reset the ECM and the IAC and do another 55 mph run. I'm curious as whether the stat change will resolve my high idle. I did not "clean the garbage" from the file before View. I'll do that with the next run. I'll post those files and then we'll see.

So far, quite frankly, I haven't seen any Sensors reading abnormily? But the engine is truly not performing at best?

Marc in sunny Titusville, FL
85 Sport Coupe w/V6 transplant
85 GT newly acquired - not on the road yet
84 SE son's car - low mileage, loaded w/options

Like I emailed, just ignore the promID it's just a number and always stays the same.

Many miles are on the engine? I just helped a friend that was having cold start and idle problems. Winaldl shows everything was ok as far as sensors, int etc. Engine ran fairly well after it was warm.
Since fuel, and sensors were ok we changed the distributor and all the problems where gone. The shaft had a fair amount of play. I wonder if it cause the pickup signal to be weak since the air gap varied.

Marc, Don`t keep re-setting the ecm for each run/log --it has to re-learn each time you do this, if you have installed a new iac it will re-seat after you hit 45mph...