2.5L ('98-'01) 2.5 rough idle while warming up

[Bunger317]

Making some progress. Finally found a pretty large exhaust leak on the exhaust manifold mating surface to the head. Also found one coil isnt firing cylinder 1. Ordered 2 coils, a set of injectors, a timing belt/tensioner, and a gasket set. Also have a rattling noise sometimes when warm so I'm going to pull the valve cover and have a look at the valve train and make sure there's no broken rockers or anything. If all this doesn't fix it I'm 100% out of ideas lol. Will post up after I swap everything. Anything in particular I need to look out for on the timing belt aside from insuring the marks are lined up?

 

[Bunger317]

Replaced the coils tonight and it made a huge difference. Idles smoother and down to 750-800 vs the 850-900 it was at before. Also seemed to smooth out fuel trims and o2 voltages. Still going to do exhaust gasket and injectors and timing belt this week because I already paid for it all.

 

[Bunger317]

Got it torn down this far to replace exhaust manifold gasket and injectors. Check compression again and had 165 on al 4. Think I should have the head rebuilt anyways since I'm this far? Everything looks ok visually but it also took awhile to get this far don't want to do it again lol

alsoit seems like my egr vacuum solonoid isn't working. Air blows through both holes. No clickingor anything when I put 12v to it. Wonder if that could have been my problem? Even with no cel?

 

[Bunger317]

Going to pull the head and have it rebuilt. Pretty sure the have the recessed valve problem alot of other people have. Tried a leak down test and had a prettt good amount of air leaking out of the intake and exhaust valves

 

[Bunger317]

Not sure why I'm updating since no one seems to give enough of a f*ck to reply but just in case someone else comes across this with the same problem. All 4 exhaust valves were recessed. Head rebuilt along with new injectors and timing belt. Purrs like a kitten.

 

[scotts90ranger]

That's good to know, were they able to put inserts in the stock head? I imagine my 2.3L will suffer a similar fate at some point

 

[Bunger317]

That's good to know, were they able to put inserts in the stock head? I imagine my 2.3L will suffer a similar fate at some point

it had hardened inserts from the previous rebuild that he was able to clean up.

 

[Brant Kieffer]

I have a 94 that has had the same problems as yours, I’ve replaced from head gaskets up and can’t seem to find the issue, the only other thing that I’ve been working on is my pcm, I’m not sure about newer models but my pcm has a few radial capacitors that leaked and destroyed a few of the traces on the board. I’m currently in the process of repairing it. I don’t know if the newer pcms had it but it may be something to look into