Expert: Roland Finston - 7/7/2011

Question
Roland, Last night as I was on the freeway the car seemed to miss fire and was running sluggish. I came up an incline and gave more gas and the rmp went to 3000 but the car was slowing down I pulled over  and popped the hood the radiator was over flowing and the exhaust manifold was glowing red hot. I could not get the engine to rev over 700 rmps and very rough idle. The last 2 weeks a few times I would be cruising along at 60mph 2000 rmp and the tach would go up to 2300 rpm and back to 2000 rmp and then not do it. ??? Any help would be much appreciated. JJ

Answer
Hi John,
I would first try to get fault codes using the ignition key:"on-off-on-off-on and leave on" doing that in 5 secodns or less elapsed time. Then watch the check engine light which remains "on", to see it begin to flash, pause, flash, etc. Count the number of flashes before each pause. Then repeat the process to assure an accurate set of flash counts. Then let me know the counts in order of appearance.
Because of the exhaust manifold showing red hot I would speculate that there may be an obstruction to the flow of exahust gas such as a honeycomp inside the catalytic converter having shifted off-axis so that gases can't get through freely.
Roland
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