Experts...Please take a look...Strange

Billabong089

Registered User
My car is gradually declining to garbage...

When I turn the key the engine self test automatically goes on until I start driving ... I have a new EEC coming shortly.


Ok besides that problem, when I drive it, you can feel it hesitating, bucks under boost. Runs very rich, carbon buildup at end of tailpipes and back bumper - Black smoke when you get on the throttle.

The check engine light flashes on and off all the time but it doesnt stay on.


Things I have done.

Just replaced coil pack today - no change.
New O2 sensors, New Plugs/wires - 2months
New Cam sensor - 1month


My friend has an expensive scanner... shows real time data of the EEC... the o2 sensors usually are low voltage and often read "INVALID"

Here is the print out...

1992 Thunderbird September 15,2005


Trouble Codes

KOEO Codes
172 Lack of Heated Oxygen Sensor switches indicates lean bank 1
538 Insufficient RPM change during dynamic response or goose test KOER or Invalid cylinder balance test due to Cylinder Identification sensor failure
Memory Codes
KOER Codes
137 Lack of Heated Oxygen Sensor switch during KOER indicates rich bank 2
225 Knock Sensor not detected during dynamic response KOER



Operational Data


##
Parameter Name
Value
Units (if applicable)



1
Engine Speed 652.00 RPM

2
Spark Advance 24.70°

3
Intake Air Temp 1.5 Volts

4
Engine Coolant Temp
199.60
°F

6
Throttle Position
0.90
Volts

7
Vehicle Power
12.50
Volts

8
Injector PW
4.90
ms

10
Idle Air Control
41.90
%

11
Vehicle Speed Sensor
20.00
MPH



12
Oxygen Sensor
Invalid

13
Brake (BOO)
Off

14
Park/Neutral
Yes

17
WOT A/C Cut-Off
Yes

18
Loop Status
Closed

19
Power Steering PSI
Yes


Ok these o2 sensors ARE BRAND NEW... I dont understand...How can I mess it up, I screwed them in and plugged the harness in... argh

I got a brand new knock sensor... don't see how that went bad... didnt put the new one in yet.

Observe number 18, Loop Status CLOSED.. what does that mean? Another test done 4 months ago read OPEN.

Guys im desperate here... I'll be willing to pay someone if they can tell me the correct thing to fix lol... PLEASE!
 
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Sounds simple to me, you say you have a new EEC coming? all of that data is pooled and distributed to your tester through none other than the EEC right? I would replace that and then see what you get.
The open loop is for when the vehicle is cold, instead of using the maf sensor and HEGO's to determine the fuel curve, it uses a set value that is way richer than normal (smoke, carbon buildup, hesitation). Sounds like your car is stuck in this mode, maybe due to the EEC, and its causing your sensors to be "invalid" or not read.
 
Yeah, as long as you've got a computer on the way you might as well wait and try it before getting too much into other diagnostics.

Did notice a couple of interesting items in the data posted

7
Vehicle Power
12.50
Volts

Kinda low. I would expect more like 13.5 to 14.5

8
Injector PW
4.90
ms

Waaaaay too much for idle. Should be down around 1ms idling. This indicates the computer is under the impression that the engine is under heavy load.

11
Vehicle Speed Sensor
20.00
MPH

Were you moving or not? If not, then something's up here.


14
Park/Neutral
Yes

Now if you were moving this should be NO.

17
WOT A/C Cut-Off
Yes

We saw earlier that the TPS was at .90 so there should be no reason for WOT A/C cut off unless the computer thinks the engine is loaded enough to call for it from some other sensor.

18
Loop Status
Closed

But apparently the calculated load is not enough to cause it to go open-loop
19
Power Steering PSI
Yes

So you were doing powerslides then? :) Apparently the EEC is under the impression that PS pressure is high.

Personally I'm not convinced that the EEC is the main culprit. I'm leaning towards a harness issue but, like I said, since you've got an EEC on the way it's easier to try that than get into pinpoint testing.
 
Well another crazy thing it does is the Auto-self test mode, I put the key to run position and guess what... the check engine light flashes and the fuel pump starts to prime and the engine goes in a self - test mode...

I start the car and the engine rev's up to 2000rpm and does a self test mode... this car is haunted or something...

If its not the EEC then it has to be a harness and theres like how many? 50 million... excellent.


Also I was moving and i'm not sure when the scanner captured that data... but whats up with high powersteering pressure? what exactly does that mean.

Also spent $90 on gasoline and its just about two weeks and im on empty...

$20 didnt even last me two days.. ($3.37 a gallon)
 
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I dont think fuel pressure is an issue. had that checked today... its 34psi at idle, when you go to start it up it jumps to 42-44psi and it holds the pressure no problem after the car is off...

The pressure went up accordingly to the boost etc...
 
I notice in your signature...

that you list a "performance chip" as one of your modifications. Could the chip have something to do with the performance problems? (if you still have it installed) Just a thought...
 
Argh , i wish more people would give me an input... I've posted like everything i could possibly post, Engine data, Codes, etc and barely anyone replied.

IF anyone can give me an idea I'd apprecaite it....


I hit a bump and the car shut off today by the way and I've noticed it hestiates sometimes if the road gets bumpy ... maybe a lose connection?

Still doesnt explain why the car goes in self test mode everytime i turn the key
 
It sounds like you Need a DIS module. Does your tack jump around? IF that is not it, check some of the grounds that go to like the rear of the head and those sort of things. Check the MAF sensor. I dont think the PCM will fix it but it wont hurt to try. If all of that fails...Ill buy it from ya for a cool fifty bucks.

Chris
 
Hey, give me a call....

I'm located in New Jersey and have a Snap-On Scanner. I can try to help you with this.

I agree that the values you have are screwy and I actually need more info, (like were you moving?????......did you goose the throttle while the test was going????.....)


Call me at (973) 277-4294


I'm in North Jersey.



Don

President....NJTACC
 
yea we were moving around... DIS doesnt fix it... I have two other ones that I swapped in...


This puppy runs rich like real rich... a puff of black smoke comes out when i started it up and when i rev it in idle... a nice puff of black smoke


Good to start running rich when gas prices go up.. how nice.
 
Carb and choke cleaner around the intake AND the IC tubes/top. Pull the vacuum off of the fuel pressure regulator. I have seen this once. The thing has normal fuel pressure and the diaphram is fuct. It leaks into the vacuum hose and runs soo rich there is black smoke.

Chris
 
As for your drop out, clean your battery posts+clamps with steel wool.. even if they look clean. Then clean your engine groundstraps and make sure they're snug. The ones which bolt to the engine mount brackets and frame.

Have you run a cylinder balance test? Its the last part of a KOER test. It should peg which cylinder is giving you a problem and hence which injector is possibly sticking or which plug boot is loose... ;)

The lack of O2 Sensor inputs sounds like a wiring problem or EEC ground problem. Look around the harness and do a wiggle test.. thats where you grab clumps of wires and shake them around to see if they suddenly work again. :cool:
 
Wow.. can I just say wow... I cant believe a $20 part would fix my troubles... wow...

I replaced the ACT- Air charge Temp sensor... no check engine light anymore coming off and on, no hesitating when driving, almost all my problems are fixed, the o2's are switching again and the guage is also working (doing its light show).

I still think the ECM/EEC might be faulty, since it does that wierd reving up thing and self test mode... but I'll investigate that further...might replace it just for fun...


Now since its been running so rich for so long, do you recommend that I change my plugs and and o2's once again? I could probably clean the plugs, (autolite double plats) but if I go through the trouble of taking them off, what the hell i should replace it... but the o2's are new but are probably shot since its been running so rich?

Suggestions/comments?

Did anyone know that the ACT sensor had that much control over the engine? wow... I cant believe it... seems too good to be true.
 
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The rev up thing is normal in self test. That is if the tester is attached. If its still revving up when you start it the yes you still have a problem. The ACT causing all your problems? Im kind of skeptical but if it was bad and shorting inside I can totally see problems. Your O2s will be fine. If you take the plugs out and clean them (if they are new) you will be okay to reuse them.

Glad you got it right.

Chris
 
unfortunatly , no tester attached looool...

Put the new sensor in and reset the EEC and so far no codes or C/E light ... running much better and the o2's seem to be working... we shall see.. if it goes back then I definatly feel its the EEC.
 
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