I've about had it with this non-sense. I just pulled the intake to make sure all the plugs we're gapped correctly, wires on good, vacuum connections seemed ok, all that stuff and the truck is still not running smooth. I have replaced the plugs, wires, fuel filter, both O2 sensors, checked for vacuum leaks, and I have no codes. I also noticed that when I pulled the PCV valve, the screen that it sits on was all gunked up so I cleaned that thinking that that was part of my problem but it didn't seem to help. I take that back, it seemed to run a little bit better but it could have been my imagination because today it was just as bad as before. What's next? I am down on power for sure, I just doesn't seem to rev freely or something. I get a little shudder when when start out too. No slipping though. If I'm on the highway and try to accelerate in 4th or 5th it pings like an idiot. Sometimes on take off while I get that shudder it pings as well. These things seem to happen more as it heats up but that may be my imagination. What is next on the list to check out?

 

I'll add that it's a 2.5 5 speed with about 150k on it.

 

pinging and worse when heats up sounds like catalytic converter stopping up on ya

 

x2

 

I thought about that, but it is less than 2 years old and I didn't think it would be bad already. How can you test it without taking it off. I'll also add that I cleaned the mass air sensor too.

 

2 yr old......150K?? do you sleep?? you cant check it but if you have a bracket behind it holding it to exhaust u can gut it with a piece of pipe and hammer......or easier pull the o2 sensor out before cat and see if it runs better....will be loud as hell though but help narrow it down

 

Is it possible that the timing slipped? If it advanced, it would explain the pinging.

 

"2 yr old......150K?? do you sleep??" Ha, sorry I should have been more clear. The cat-pipe is 2 years old, the truck is a 98.

I'm thinking the timing is off. I bought a new timing belt to put in tomorrow. I figure even if that's not it then it could still use changing at this point anyway. If I put a timing light on the #1 plug wire should I be able to read 10* at idle? I've only messed with the timing on an older mustang I had so I'm not sure if it's the same. Also, does it matter which #1 plug wire I put it on since there are two wires per cylinder? Thanks!