Rough idle,stuble start

[clieman]

Hello all! I need some advice. Im am looking at a potentially very expensive repair and want to make sure that it will address the problem. I have a rough idle and it almost dies when I start it when its warm. Supposedly the O2 sensor is gone; my tech tried to "clean it" without removing it and the problems started after that. The problem is that my exhaust is so rusted that they cant get the sensors out! It will require removing the whole downpipe (which they say will cause the bolts to snap and break because of the rust) in order to heat up the pipe enouogh to remove the sensors and replace them. There is also a risk that they will need to remove the whole manifold in order to get them out, depending on the rust plus they may strip out the bolts in the crossmember causing more issues. I can get a new downpipe assy for 630 from atlantic british, they havnt quoted me on the above repair yet, but he said it will be cheaper than a new pipe. Suggestions?????
Oh, 01 DiscoII w/ 75k.

 

[joey]

are you getting a code for the O2 sensors?

Spray the O2 sensor down 3 times a day for 2 days with penetrating oil then remove the O2 sensors...

Here are some other tips http://www.film.queensu.ca/cj3B/Tech/BoltRemoval.html

 

[clieman]

The shop cleared the codes (at my suggestion) so the computer would get fresh codes (I had just replaced the MAF). It came back on the next day. I’m taking it tomorrow to get the codes read.
BUT, should I try soaking that thing for a few days with penetrator before I dump at least 350 for the shop to take the pipes off the truck? I don’t think there trying to rip me off; they sounded like they didn’t want to run into extra problems, either. I mean, the rust is evident, but it’s not eating through and causing holes or anything (yet). Also, have a good suggestion for a product that can stop or slow-down underbody rust? I live in Cali now but the car obviously came from Colorado or somewhere similar.

 

[joey]

If it were me, knowing that they are already bad... I would either spray them down or get a pipe wrench and remove them. What is the worse that can happen you have to take it to the shop and change the y pipe... you are already planning that.

Underbody rust... I would suggest a good wire brush and remove as much rust as you can. Or buy a large bottle of "Navy Jelly" it turns rust back into metal... then prime and paint.