1990 TPI/350, speed density.
Set timing with the tan wire unplugged to 6 degrees.
Just replaced all spark plugs
three month old injectors.
37PSI of fuel and holding after the vehicle is turned off.

I have no VSS.

This engine ran great, just a little rich, but all of the sudden its running richer then I ever thought an engine could run!

Not sure if any of this info is not needed, but this is all that my scanner tells me!

Its running so rich that its blowing a fuel/smoke out of the exhaust.

blm: 30
blm cell: 4
ccp duty% =0
ccp solenoid off
coolant - 199
engine rpm 825-850ish
exaust 02 switching between lean/rich
iac pos: 117
idle req rpm 700
inj pw (ms) 1.8-1.9
integrator: 132
knock ret - 0
knock sensor:16
loop- closed
map 1.3
mat 137
02s MV: 250-700. (bouncing constantly)
o2 crosscounts - 10 additions per second (on average)
oil temp: -39F
pn switch: r/dl
spark advance: 22-23
throttle: 1%
tps sensor: 1.00V

 

What is the coolant readout?

Is it -199 or 199

 

I messed up! It should be =199

the only thing that is not working is my oil temp sens, which I don't have

Before I had a scanner, I measured resistance on every sensor to make sure it was within spec.

this is really kicking my butt!

If it matters, I have a complete new exhaust system, and they welded in the o2 bung on the driver side right after the collector from the headers

 

Looks like you are running lean to me... unless SD is backwards from MAF.

 

SD backwards from MAF?

English please! lol

 

I was looking at your BLMs. BLMs of 128 are stoichiometric (14.7:1 Air/fuel ratio). Anything higher than 128 should be lean. Anything lower should be rich. At least thats how it is on a car with MAF. You said you have Speed Density. I have never touched an SD car but I assume they are the same. So to me, it looks like you are "way lean" instead of "way rich."

I am sorry I can't explain as to why you are lean, but from the looks of things, you are.

 

Ok, I gotcha now. I'm not very knowledgable on either

This is what baffles me, the scan results look fine, at least from things I have compared to on the searches on this site. But Its running so rich that your eyes burn, and it shoots out almost raw fuel out the exhaust.

If I run the engine slowly up to 5000, its just really bad. When I let off the gas, it shoots out a huge cloud of gas/smoke.

 

Wait a minute, I am an idiot! I kept thinking I was seeing 130 BLMs... not just 30 BLMs! Sorry for the mistake. Then your computer does see you as running way too rich... The only think I could think of is a bad o2 sensor...

 

So these numbers here:

02s MV: 250-700. (bouncing constantly)
o2 crosscounts - 10 additions per second (on average)

don't mean a rich or lean issue? How can the o2 sensor be giving bad information, if the stats above are in the norm? Or are the o2 sensors results way off from the norm?

btw: I really appreciate the help!

Something else to toss in here, I had somehow lost the ground to my distributor right before this started happening. It was arcing on the block, and stupid me just put a wire nut on it, and drove it. I didn't put it together what it was. Since it was still running, I thought it was just a sensor wire.

Well, I ended up re-grounding it. Could it have been deriving ground through the tach, or through the module? Could I have a bad module? Is running rich a normal issue when it goes bad? I ohm'd out my coil pack, and it is fine.

 

When it comes to the o2 volts: 450 is another way of saying 14.7:1 A/F ratio. In order to keep a car running as clean as possible, it needs to constantly go from rich to lean and back and forth. This helps the cat put out as clean of air as possible. So, your computer is doing whatever it can to make your o2 sensor constantly bounce between roughly 150-850mv. So you are going rich/lean/rich/lean/rich/lean. That is pretty much the purpose of closed loop fuel control. If, however, your o2 sensor starts sticking towards say 100-200mv, then the computer will try to richen it so that it can get back to the rich/lean/rich/lean stuff. So, 450 is stoichiometric, anything below is lean and anything above is rich. Your computer tries like hell to keep it going rich/lean/rich/lean etc... It does its best not to let it stay too rich or too lean. It can only fix something so far though. Soon it will hit a wall and say "I can't fix this anymore!" and that is usually when you throw a code or something. If I explained it right, then you should see how an 02 sensor giving bad info can cause a car to run too rich or too lean.

In a nutshell, even though your o2 sensor looks like it is in the proper range, the reality could be much different.

I have not yet learned about o2 crosscounts... can't help you there.

I am also not really sure what a typical condition from a bad module would be.

Do you have a volt meter in which you can graph out your o2 sensor? You might be able to try the propane trick to find out if it is bad or not.

Also keep in mind that I am no expert. If anything I am saying is wrong, I hope someone would come in and educate us both.

 

update.

Swapped out ignition module, coil, o2 sensor, and map sensor. Same result.

Just ordered a new prom.

 

is the data while the car is idling becuase the tps seems a little high for idle. also what car is this in. look up the specs for each sensor. but the tps voltage seams a little high to me when you arn't on the throttle.

 

Could the headers and new exhaust not be allowing the o2 sensor get hot enough, I have read a lot about the necessity of switching to a heated o2 after upgrading to headers and better exhaust due to lack of heat in the collector.

PS. Camaero, did you upgrade danelU's car to $6E, or did you leave it $32B, I really need to come down and hang out with you for a weekend to pick your brain.

 

umm same problem swapped out the ecm and the problem was fix

 

personaly, whenever i replace an O2 i go with a heated one.

 

I fixed it!

Had a hole in piston #8. I'm guessing due to detonation for running without a knock sensor.


Replaced EVERYTHING down low, block/pistons/crank/cam/, and the thing runs like a raped ape.

I spent 5 days troubleshooting, and 3 days replacing the block.

Wish I would have just done things right and did a compression test on the first day.. Oh well, good as new! I welded a bung into my fuel pump blockoff plate and installed a knock sensor. Hopefully this won't happen again.

Thanks for the help!