93 850 only runs when cold

[johnsykas]

My son's 93 850 just stopped running one day. It turned over fine but would not quite start. It was very low on oil. We put oil in it and changed the plugs and it ran fine. The local dealer told us it was the fire trap and needed all new engine seals. I replaced the fire trap and blew out the line (old trap seemed fine).

After running about 15 miles the catalytic converter caught on fire. he did get he fire out. We changed the cataylic converter and it ran great for about five miles, then ran very rough like it is flooded.

The local dealer sasy it is the a clogged ventilation system. They also wan tto relace all the seals. I can not see doing that as once the converter was replaced we lose no oil.

Is there a sensor that could be malfunctioning? Is there an cold start injector that could be stuck? Something clogged teh converter and fouls the plugs.
Any ideas?

[dpauto.com]

Obviously the dealer did not know what the heck they were saying. I would check the fuel pressure and monitor it as the engine is running. Also check the coolant temp sensor to make sure its not shorted.

Dave

[johnsykas]

It was the fuel pressure as you suggested. I took the fuel rack off my wrecked volvo and exchanged the catalytic converter and it runs fine. I did not have to change the engine seals & flame & engine ventilation as dealer wanted to do. saved $1,500
John