I have a 95 ram 1500 4x4, 5.2 and the other day the catalytic converter plugged and melted part of the egr valve. I blocked the vacuum hose to egr valve and put a block off plate on egr valve. By the way converter is now gone. The problem now is engine now idles way too high (1250 in park and 1000 in gear). Can anyone point me in the right direction?



Thanks,

 

the rom was pointing me in the direction of a vacuum leak because i am throwing a code for target idle not reached and it idles at about the same i replaced the iac thinking that might be it but it still did it so i would check vacuum lines

 

Thanks, I'll look for vac leaks and check the IAC. Before the Cat plugged everything was fine. I'll let you know!

 

Welcome to DF!

The cause is your EGR valve You blocked the mounting hole off, but you didn't actually block off the exhaust gas crossover...the passage that feeds the exhaust to the valve, which is part of the intake manifold. If I remember right, these motors have a "plunger" style EGR. When the EGR is closed, the plunger is sucked up towards the valve...closing the passage. When it is open, the plunger is down, letting gas pass through. So basically, your EGR is "wide open" right now...nothing is stopping the exhaust gas from passing into the engine. You either need to re-install the EGR in such a way that the plunger is always blocking the passage....or find some other way to block the passage, or just replace the EGR valve.

The other thing to do would be to make sure you're not leaking vacuum...from both the line you plugged off, and anything else you may have melted.

I don't think your EGR melted because the cat was plugged either. I have a feeling you were running rich, and that's why your cat plugged/the valve melted. A plugged cat wouldn't melt the valve...it would just diminish performance in the higher RPMs, and possibly cause some idling issues.

EDIT: Actually, after looking at a picture of the valve on rockauto, it looks like it's a 2 hole style (in-out) EGR valve. I guess I should've just asked you what the hole in the manifold looked like when you removed the valve. If it's that style, you have to make sure the "bridge" between the two holes is blocked off. If it's not, you're still circulating exhaust gas....ALL the time without a valve.

 

Thanks for the help guys, I'll change EGR valve tomorrow. One comment on last reply, I never had any engine codes or check engine light. If it was running rich wouldn't I get a code for the o2 sensor? The ceramic comb was literally broken in pieces when I removed the cat! Will repost after I fix problem.

 

Nope...it's common (especially on pre-odbII vehicles) that a rich condition won't set a code. [&:]

 

Thanks for all the help guys. Changed O2 sensor and EGR valve and running just fine now.



Giddy