help identifying this part

can anyone tell me what this part is? It looks burned. It is on the firewall. This is an 87 Buick Riviera with 92,000 miles. One owner.

can anyone tell me what this part is? It looks burned. It is on the firewall. This is a 87 Buick Riviera.

Nothing to look at?

I am having a hard time with pictures.

Probably something electrical and drawing alot of current.

looks like a relay......fuel pump relay? ac relay? cooling fan relay?does car start........any burned out fuses?

The car runs pretty good. I get a message on my CCC that says my Engine Control Module needs servicing. It stalls sometimes. When I try to pull codes with a paper clip, the service engine light just starts flashing real bad. I have this posted on 3 forums and no one knows what it is!!!! I find that strange. I would think someone knows what it is. Maybe not enough people are reading this post.

the field service mode has 2 forms......key on engine off and jumpering terminals a and b of the 12 pin alcl connector and using flash diagnostics count the flashes.....also if car is running the ecm will display oxygen sensor status through the check engine light....if light is flashing very fast about two times per second indicating the ecm is in open loop and after enters closed loop the light will stay on during rich condition and off means lean condition......you want to check codes koeo key on engine off and count flashes in numeric sequence.

I turn the key on, insert the paper clip to short the terminals, and then the light just starts flashing about once a second and never stops. It gives no read outs or anything. I can go to the CCC and go to Climate control, push off and warm at the same time, and enter the service mode, and pull up some codes. But as far as pulling up the codes off of the flashing light, I can't. I am not even sure the Riviera will let you do that.

get a subscription to alladatdiy.com and find out what relay that is and also look at wiring schematics for that relay.......it should be fuse or fusible link protected.know anyone with a scan tool to see if communication is possible with cars ecm?

Here are a couple more pictures.

This is another one. I have alldatadiy.com and I can't find a schematic for what this is. Alldatadiy.com is hard to navigate. Lots of jumping around, back and forth, etc.

here is a schematic from alldatadiy.com

It is a connector. The two parts push together and held that way with a screw. It runs back inside the car.. It looks like it got hot and parts of the asphalt or what ever it is inside of them, melted! The prongs look like they have it all over it too. I am at a loss now. It is not like a part that can be replaced. If I clean it up good, I still have not solved what got it so hot. No fuses anywhere are blown. Any ideas?

**************************************UPDATE.

I did some more research and it seems that black asphalt is actually black di -electric goop from the factory! So I am putting it back together, unless someone can tell me why i shouldn't.

engine dash harness connector........do wires go to fuse block or to ip inside car?

a.k.a. "Bulkhead connector" in most cases. Since the connections are sealed with tar putty to prevent moisture incursion, you may just be seeing the tar running out of the housing from the effects of 25 years of gravity pulling on it.

Since the Riv/Riv-T has the DIC in the dash the ECM operates a bit differently. I've only worked on two of those (one in an Olds Trofeo) and information is scarce. They used a low baud rate serial interface with the ECM and the body modules. I can't recall if jumpering the ALDL A-B pins was still an option for strobing the MIL to retrieve codes, but if you can find an older Snap-On MT-2500 scanner or GM Tech II it should be able to retrieve all the data, and possibly operate some of the devices remotely.

Something that old, I doubt you will get parts for....

Here's what I would do......seperate the connector....what happened was, you have male and female connectors coming together....when the female connector gets loose or spreads, you don't have a tight connection.....this may cause arcing and a build up of carbon....this create resistance and heat...it can get hot enough to melt the plastic around it......

What you have to do is find the bad connections(contacts will be black and surrounded by melted plastic, or if you had a spare male connector, you would do a "drag" test on each female connector).......when you find them, cut the circuit on both sides of the harness, and hard wire them together with a short piece of wire(soldered preferred).....

a.k.a. "Bulkhead connector" in most cases. Since the connections are sealed with tar putty to prevent moisture incursion, you may just be seeing the tar running out of the housing from the effects of 25 years of gravity pulling on it.

Since the Riv/Riv-T has the DIC in the dash the ECM operates a bit differently. I've only worked on two of those (one in an Olds Trofeo) and information is scarce. They used a low baud rate serial interface with the ECM and the body modules. I can't recall if jumpering the ALDL A-B pins was still an option for strobing the MIL to retrieve codes, but if you can find an older Snap-On MT-2500 scanner or GM Tech II it should be able to retrieve all the data, and possibly operate some of the devices remotely.

I took this video of the dash trouble codes, but I can't make anything out of it.


http://youtu.be/Vrao5WDVfk4

So you have the CRT display....this is like having your own Tech I scanner built into the car....SO YOU DON'T HAVE TO INSERT A PAPER CLIP INTO THE ALDL CONNECTOR......you have the info on the screen of the CRT....you are very lucky it is still working....FYI, under the center console is a very expensive power supply for the CRT and for your digital dash....never have a cup of coffee or liquid in that area(spills are a no-no)....

Watching you go through the scrolls, you cleared the codes....next time the check engine light comes on, go into diagnostics, and when "ECM codes?" shows, click yes....then it will give you the codes in the car......keep clicking yes to see all the codes set.....

As you were scrolling through "ECM data", I noticed that O2 voltage was low and there were zero cross counts....this means the engine is running lean....also IAC counts were high, to keep the car running(either A/C on or throttle plate and bore are dirty/gummed up......block learn was set at 128 because a code is set.....

You are lucky to have a functioning CRT......it's better than most scanners out there.....

I turn the key on, insert the paper clip to short the terminals, and then the light just starts flashing about once a second and never stops.

You need to insert the paperclip before turning the key to the Run position.

As for the "melted" look, I've seen that same stuff on several older GM connectors. I think it's something to keep moisture out of the backs of the terminals.

-Rod

So you have the CRT display....this is like having your own Tech I scanner built into the car....SO YOU DON'T HAVE TO INSERT A PAPER CLIP INTO THE ALDL CONNECTOR......you have the info on the screen of the CRT....you are very lucky it is still working....FYI, under the center console is a very expensive power supply for the CRT and for your digital dash....never have a cup of coffee or liquid in that area(spills are a no-no)....

Watching you go through the scrolls, you cleared the codes....next time the check engine light comes on, go into diagnostics, and when "ECM codes?" shows, click yes....then it will give you the codes in the car......keep clicking yes to see all the codes set.....

As you were scrolling through "ECM data", I noticed that O2 voltage was low and there were zero cross counts....this means the engine is running lean....also IAC counts were high, to keep the car running(either A/C on or throttle plate and bore are dirty/gummed up......block learn was set at 128 because a code is set.....

You are lucky to have a functioning CRT......it's better than most scanners out there.....
++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++++++++++++++++++++++++++++++++++++++++++++
Wow, thanks. I ran the codes awhile ago and got the EO24 CODE, AND THE EO44 CODE.


E024 Speed sensor Circuit problem VCC, CRUISE
E044 Rt. Oxygen Sensor Signal Lean / AIR, CL canister purge
************************************************** **********
alldatadiy.com for my car says the EO24 is vehicle speed sensor circuit failure (*TCC)

AND EO44 is Lean exhaust indication.
************************************************** ***
This goes along with what you were saying earlier, although it goes over my head how you figured it out just by the video!!

I am wondering to myself is the fact that I have a lot of that Sta-Bil in my gas tank has anything to do with the lean exhaust? I know when I first crank it up, it wants to die, and coughs, but then after it reaches about 180 degrees or so, it smooths out.

Any ideas?

Having a 20+ year old oxygen sensor is probably part of the problem. Double check the connection to the sensor just to be sure, but I suspect your old sensor is, well. OLD. A replacement single wire sensor is about $25 and you could save that much in fuel alone in the first thousand miles.