1991 volvo turbo idles and runs ok exhaust manifold gets glowing hot after highway speeds checked and repaired all vacuum leaks had replaced air mass unit before this happened. timing by the book 12...
The Garrett turbo-charger is notorious for leaking oil into the intercooler, and, into the emissions system. This happens because the bearing wears in the turbine assembly, and dumps lubricating/cooling oil into the combustion and intercooler system. It also ruins all of the rubber hoses that come in contact with the oil.
A result of this, after thousands of miles of driving: Your catalytic converter is clogged. The backpressure from the clogged exhaust increases the manifold temperature to cherry hot!
When I had my Volvo service and sales business, I lost money on only one Volvo; a turbo-charged 1988 wagon! A friend of mine who made his living salvaging Volvos had similar experiences with turbo-charged 240's and 740's. I hate to break the news to you my friend, but you will need to spend lots of money on that vehicle.
Trust me, do not try to fix it as it's a black hole---$700-900 for the rebuilt turbo ($250 for the rebuild kit), $200-300 for the catalytic converter and on and on! When I bought that vehicle from the original owner, It had a stack of repair receipts an inch thick!
The only recommendation, if you must keep and drive the car: remove the turbo-charger, intercooler, and all attendant hoses. Replace the air assembly with one from a normally aspirated B230F, and keep the airmass you just installed. Replace the catalytic converter with a good used one if you can find it.
Mar 25, 2009 |
1991 Volvo 740