best OBD1 scantool?? Misfire/backfire ? at cruising speeds 65-70

[jrollings]

hello all,

I've been having an issue with the Burb ever since I traded for it. At highway cruising speeds 65-70 I get a surge/buck/misfire. I can go WTFO and not have any issue but trying to maintain cruising speed this happens. It did happen tonight on cold start up when I was leaving work. Felt like its just falling on its face. Once I got home I sprayed the wires in the dark hoping to find a fireworks show only to not see any arcing at all.

I have searched. The truck has almost 213k on it so its broke in a little. Is there a way to check to see if my distributor gear is worn without pulling the whole thing? I know diesels like the back of my hand but I'm scared I wont get it back in the correct spot/ tooth orientation if I do pull it out even if I mark it.

Any help here is appreciated. The previous owner said a tune up was performed about march of 2014. I did just go pop the distributor cap off. The cap, rotor and plug wires are new. The distributor tabs inside of it are wearing on the edge instead of the middle like I thought it should but maybe that's because its new? idk

BTW, no codes are present, It consistently flash 12 when I use the ole paper clip trick.

 

[SkyHighColorado]

Tunerpro rt

Just buy an obd usb cable on ebay then download the files you need by looking up you ecu's serial number. pain in the ass to set up but worth it when you can data log and see whats going on while driving or whenever.

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probably some stupid egr bs. delete it.

 

[jrollings]

Thx SkyHigh....I found the tunerpro right after I started this thread, so no need to know the best scanner obd1 wise. I'll do that here in the next week or so hopefully. EGR valve is new by the looks of it. Can I just unplug it tomorrow on my drive into work to see if that's the culprit?

 

[98_k1500]

Could you walk me thru the obd-usb cable and computer thing?? i really need this for the camaro and don't really know where to start.

 

[Big98z71]

I would be looking at the ignition module and coil

 

[jrollings]

I would be looking at the ignition module and coil

Can I have an explanation on your thinking here? Just curious because with my experience when the ICM is gking bad it kills spark when the ICM gets hot? Not arguing just trying to educate myself some.
Also, the coil, will an ohms test show bad even though I'm mainly at cruising speeds?

Thx for the replies everyone

 

[jrollings]

Bump, any other ideas?

 

[SkyHighColorado]

Could you walk me thru the obd-usb cable and computer thing?? i really need this for the camaro and don't really know where to start.

yeah, I am not a pro at setting it up but I can help you out. It wasn't easy to start data logging.

So just google tunerpro rt. must be the rt version to data log in my experience. download is free.

Count how many pins your obd port has under your dash because there are 2 different ones, I think 95 may have more pins or something.

Order the OBD to USB cable on ebay. With the correct number of pins.

Pull your glove box out. Pull the ecu out. take a photo of the serial number sticker on it (just take pics of all the numbers on it).

go online and google search for the ADX file that has all the information in it to read data from your ecu. There are many different ecu's out there so you HAVE to look up your serial number or it wont work at all.

Then in tunerpro you basically upload that ADX file and then you can data log and make XDL files which contain all the recorded stuff

kinda gets a lot more complicated that that but its a start. The most frustrating part is uploading ADX files and not getting and readout even though it recognized your truck. just keep trying it eventually you will get it to work. Then save that ADX file and keep it forever!.


By far the most useful mod I have done, I use it all the time. I run my laptop on the passenger seat to just be sure everything is operating alright.

 

[supertrucker1978]

Not sure why on a cold start up it was falling on its face, but the issues at cruising speed might actually be the torque converter locking and unlocking also known as "torque converter shudder". My 95 with 246K had it and it sounds like what you are having at cruising speed.

 

[jrollings]

Not sure why on a cold start up it was falling on its face, but the issues at cruising speed might actually be the torque converter locking and unlocking also known as "torque converter shudder". My 95 with 246K had it and it sounds like what you are having at cruising speed.

I read to flush the tranny to help with the shudder but I'm not sure if its ever been done so I don't want to go causing more issues by flushing it. Has anyone ever used that Dr. Tranny instant shudder fix?

It did fall on its face again last night leaving work. I went to move it up closer to the building after about an 8 hour cold soak. I then let it warm up while I went inside to change and clock out. It was warmed up by the time I got back out to it and it wasn't falling on its face any longer.

this is very irritating and has me stumped. I tried to check the timing lastnight using my actron timing light with built in advance. I marked 4* on the dampner after cleaning it up so I could see it. I then disconnected the tan/black wire for the distributor. Once I started the truck, I noticed the timing mark moving all over the place. Am I doing something wrong? I never claimed I knew how to time this thing.....

This burb is making me miss my compression ignition vehicles....