Bucking frequently now even at low RPMs

[SenorNoob]

I just did mine a couple days ago. I pulled the 2 screws holding the sensor into the housing pulled it up and out. Then hit everything liberally with MAF cleaner. Supposedly it is special, but I've never had a problem using brake cleaner or carb cleaner either...

 

[william wixon]

Thank you very much! If the air cleaner was changed recently, the spark plugs were changed recently. I never put new spark plug wires, and I have no idea how to clean a mass airflow sensor. I removed it a while ago at the suggestion of someone for another issue I was having and when I looked at it, I was like oh my God no! I had no clue how to interact with that thing and certainly not how to clean it. A very scary, mysterious electronic device.

I have never had an issue with the distributor cap and again I’m embarrassed to admit I didn’t know this truck didn’t HAVE a distributor cap! I assumed it did, it doesn’t. To me this issue seems electric or maybe even electronic.

 

[william wixon]

thank you, yeah that’s a great suggestion. I really should have replaced the plug wires. I assumed they were fine like you said they look fine They are about due for a replacement.

Embarrassed to say LONG overdue!

 

[SenorNoob]

I bought a car from mom with plug wires that looked fine till I washed under the hood cause of an oil leak. Barely got home and it looked like a Pink Floyd concert under the hood at night. 250,000 Miles and factory platinum plugs.

 

[william wixon]

I bought a car from mom with plug wires that looked fine till I washed under the hood cause of an oil leak. Barely got home and it looked like a Pink Floyd concert under the hood at night. 250,000 Miles and factory platinum plugs.

me too, it was in the 1980s. It was a (70’s) Datsun pick up. It was raining, it was dark. I was having some kind of ignition issues. I opened the hood and I couldn’t believe what my eyes were seeing! All the spark plug wires had bright electric blue fuzz on them! That’s when I realized I needed new spark plug wires. Something that I’m aware of, but didn’t think this was the issue. I just ordered some spark plug wires. I’ll let you guys know if that was the issue! I’m afraid it’s not. I’m afraid it’s something disastrous and incredibly expensive.

 

[pentode]

Moisture definitely made my cracked coil pack much worse. I found the problem because a car wash turned an intermittent misfire into running on 3 cylinders. I don't want to push that theory too hard as I figure it's a pretty random failure, but it's not an expensive fix. I think my replacement was $30.

Like I said, it was invisible from the top but once flipped over, you could see the crack and carbon tracking in the epoxy potting, is was clear as day.

I don't think anyone has asked: have you pulled codes from it yet?

 

[william wixon]

Thanks again!
Yesterday I took it out for a test drive and it seems like the bucking problem has gone away, so at this point I am attributing it to humidity, moisture and bad spark plug wires. But I would like to check the underside of the coil pack just to be sure. Thank you to you and everybody else who helped me with this really scary issue.

 

[william wixon]

Moisture definitely made my cracked coil pack much worse. I found the problem because a car wash turned an intermittent misfire into running on 3 cylinders. I don't want to push that theory too hard as I figure it's a pretty random failure, but it's not an expensive fix. I think my replacement was $30.

Like I said, it was invisible from the top but once flipped over, you could see the crack and carbon tracking in the epoxy potting, is was clear as day.

I don't think anyone has asked: have you pulled codes from it yet?

Oh yeah, sorry. Yeah, I have checked the codes, there were no codes activated.

 

[pentode]

Oh yeah, sorry. Yeah, I have checked the codes, there were no codes activated.

That's an interesting data point in itself. Does your scan tool let you see misfires in real time? I can't recall if this computer even offers that data, hopefully someone knows offhand. I'll have to check a bit later on otherwise.