1972 145E idles way too high

A very tricky car to work on, as this model is almost nonexistent! It idles so high, I don't want to put it into gear. The idle adjuster is all the way down. A mechanic told me I may need a temperature sensor, which may not be available. Any ideas anyone?

Reply to
franko77
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Something is sure out of whack. I used to have a 1970 145 here in the US, and I didn't really have any problems with the carburetor. (Don't get me started on the distributor and points, though!) It had a manual choke, too, which doesn't fit in with the temperature sensor recommendation.

The central question is whether the throttle plate is open, causing the high idle, or if the air is coming in someplace else and the carburetor is just tweaked to keep it from stalling. My guess is that the throttle is actually partly open, possibly because the throttle linkage is misadjusted. IIRC there was a turnbuckle affair in the linkage on mine - it may need to be loosened. On yours, not mine ;-)

Finally, how long has it been like this, and did it get this way suddenly or did the idle just creep upward?

Mike

Reply to
Michael Pardee

The bowl under SU's have a poppet valve in the throttle plate. If you heat the solder fixing the valve stem and spring assemblt to the plate you can screw the poppet down flush with the throttle plate surface. Clean, flux and sweat the valve permanently closed and the idle can be reset.

Bob

Reply to
Robert Dietz

On the side of the head, below the thermostat, in front of the manifolds is a valve which allows air to bypass the throttle when the engine is cold. Pinch one of the 2 hoses going to it, and see if the idle slows down. If it does, pull off the top hose, you should see an odd shaped hole with a metal cylinder that slides across to block it from below. If it's not completely closed when the engine is hot, it'll be your problem.

Reply to
Mike F

"Michael Pardee" skrev i meddelandet news: snipped-for-privacy@sedona.net...

145E= Model series 1. 4 cylinders. 5 doors. E - electronic fuel injection. Leave the carburettor guessing. Think: Fuel Injection.

//Erik

Reply to
Erik Lidén

Group,

The 145E was outfitted with the Bosch D-Jetronic Electronic Fuel Injected fuel system. No carbs. No manual choke cable on the dash. No fuel bowls.

Franko, is this still using the D-Jet, or has it been converted to carbs (SU, or Weber, or other)? Believe it or not, the conversion from carb to EFI or from EFI to carb is pretty straightforward, and somewhat common, depending on one's fuel system religion.

If still using original D-Jet, are you sure that the closed down idle screw is letting the throttle plate close completely? Gunk may have seeped into the throttle body from intake and oil, preventing closure. Has throttle switch (on side of throttle body) been cursed at or otherwise tapped/abused recently? If yes, go back to square one on proper throttle switch adjustment. Haynes manual on the 122/1800 is probably adequate, though you may need the Volvo 1800E Supplement publication for the D-Jet, if not found in the Haynes 120 or the Haynes 140.

The cold sensor valve, very close to the thermostat housing, should not have more than 500 rpm impact on your idle speed, I would not think. I think warm engine idle is around 1200, cold engine is around 1700. I'm working on memory alone, mostly in need of modern RAM upgrade. Anyway, this valve is probably a piece of ancient over-engineering, mattering little if it works or not. However, if the vacuum hoses to and from this valve are decayed, then these could affect idle.

Main common culprits on D-Jet are decayed vacuum hoses and fuel delivery hoses and seals, allowing unmetered oxygen intake to mess with your mind. You should always use fresh rubbers.

Reply to
Pat Quadlander

IPD had all the temp sensors for my '72 145E w/B20F engine; they seem to be fairly common Bosch parts. There are three--one for the intake air, one at the thermostat, and one at the right rear corner of the head. The first two are used by the FI system, the last is for the dash temp gauge.

If the wire breaks on the one at the thermostat, the engine stops.

Generally, high idle is an indication of a vacuum leak; check all hoses; also check the timing.

IPD is

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A detailed description of the D-Jetronic system and settings is at

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includes instructions on setting the TPS. As far as I know, the only impossible-to-find part is the MPC sensor; on the right fender, looks like a fat ignition coil with a tube to the intake manifold. Those are no longer made.

Gary

Reply to
Gary Heston

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