So, I've had my '98 1500 (5.2L, 2WD) for over a week, now. No problems, until yesterday. Well, I think it started yesterday.

A few days ago, I started hearing a high pitched whistle. It pretty much sounded like a mix of microphone feedback and ringing in your ears (for those of us who are lucky enough to get that). I'm still trying to track that one down and figure out what's causing it.

But, the one that bothers me more is the loss of power I got yesterday. The first thing that was strange was that soon after I had started my hour drive, I pulled into a gas station and got something to drink. After I was in the truck, I was getting situated and I heard the engine rev up. I thought that was weird and looked quick but my foot wasn't on the pedal and neither was my wife's (she was sitting next to me and I thought maybe her foot accidentally went over there since she was getting settled in, too). It went down back to normal as quickly as it went up. I shook it off as a fluke and went about the drive.

Towards the end of our drive, about an hour later, something strange happened. I had been driving at highway speeds. I stopped to turn and, then, when I pressed on the gas, it was like nothing. The truck barely moved for the first 30 seconds. I finally got to a parking lot and looked under the hood. Could not see or hear anything out of the ordinary. I throttled it up under the hood, but there was no stuttering. I checked the tranny fluid. It was just fine. Looked nice and pretty.

Got back in the truck. We were almost to our destination, so I wanted to keep seeing what would happen. At one point, when I was turning and getting no power, I downshifted to 2, it seemed to help, but I don't want to assume that was the reason. Also, a few times, when it was having problems, I heard a sort of "thunk" coming from the back. Sounded like a quiet version of a backfire. I managed to get it to the house we were going to without too much of a problem. Parked it and looked under. Everything seemed in place.

We were there about an hour and then we were supposed to have dinner at a friend's place. We drove there. No problems. After that, (it was a few hours), we drove the hour back home. No problems.

I'm going to stick a code reader on it, but wanted to see if anyone had any ideas what it might be. This is upsetting me now, because I've had no problems with it, and I'm supposed to be driving to SC with it on Wednesday. But, then, this is why I've been driving it a lot now...to fix any issues before going.

 

Has the plenum been fixed?

Sounds like the cat is going belly up. It gets hot, closes off the exhaust, and you get no power. Let it cool, and it runs fine for a while again. Trouble is, it seems to take a good bit of time for symptoms to appear...... so testing it is going to be fun. You could take it to an exhaust shop, and have them do a backpressure test, but, no guarantee the results will be meaningful. (unless it simply fails.)

 

I have not looked at the plenum yet. I was sort of thinking cat, myself. That and the tranny were the first two things to come to mind. However, my vehicle diagnosing powers just aren't up to speed yet and I'm still learning. I'll probably take it to a muffler shop to see what they can find. Gotta figure this out fast before I head down next week.

Out of curiosity, if the cat is starting to fail, about how much time will I have? I'm supposed to be towing my wife's car behind this thing (her car is light. A Corolla). It'll be about an 8 hour drive.

I'm half-tempted to say to just replace the cat, but I'm not a fan of throwing parts at something hoping it'll fix it (I'm an aircraft mechanic and, way too often, my bosses like to play "Throw parts at it!" and I can't stand it).

 

You could remove the front O2 sensor and drive it around to see if it runs better. It will cause the CEL to go on, but you can clear it after you're done. Another thought about the high pitched whistling, could be a vacuum leak. Maybe plenum. You should check that first.

 

Cat failure is unpredictable. Might go in five minutes, might go in five years..... muffler shop can kinda/sorta test it.... if its clogged, you can decide from there if you want to replace it (magnaflow high-flow cat, don't bother with stock replacement), or just hollow it out.

 

Took it to a muffler shop. Talked to the guy for a little bit and he thinks it was a fluke. He said that, if the cat was acting up, I would know for sure, and it wouldn't have been a one time deal. He said that, if it happens again, to swing it into a shop. So far, he's been right. I haven't had any other loss of power.


As for the high pitched noise, I finally thought to take off my CB antenna. Noise went away. So, now I'm trying to narrow down if it's wind noise from the coax or if there's some sort of weird interference going on.


Meanwhile, she has now decided to creak like and old man from the front suspension and when turning. Good times. I just sprayed the crap out of the front suspension with some spray to see if I can get it down. I leave tomorrow for SC. Once I get a place to live, I can devote a good weekend to doing a lot of maintenance I've been wanting to do (maint I had planned on doing with any truck I bought, since I don't know how reliable of maint the previous owners did).


I did check the ball joints because of the squeaking on turns. Solid. No play in the wheel at all. That was the only thing I was overly worried about. I have about 600 miles (already driven it about 1600 miles since I bought it) to go at highway speeds. Is there anything else I should look at in the suspension before I take off?


Based on my talks with the previous owner, I think this truck sat for a while and everything is breaking loose. Up in IN, I had the snow and rain almost every day, so I think that was keeping it a little lubed, but I'm in southern OH now, and it's dry here. Hope it's okay I just added to my thread. Didn't see a reason to start another thread.

 

If there are grease fittings on the front suspension, hit 'em all. Probably what you are hearing is dry joints.