Friends,
My son's 1986 245DL runs like stink 98% of the time, but every once and while while traveling down the road, it suddenly starts to lack power! No a miss, more like its starving for fuel. Once this occurs, you pull off the road and turn the key off, then restart the car to have full power again. So far, I've changed the fuel filter and drained the tank to check for water contamination, but no luck!
I'm up for suggestions?

I'd like to make a suggestion, it really sounds like a fuel pressure problem thats killing the engine, cruising just sucks more fuel pressure than something could hold. I'd check the pressure like the bently's guide guide.

I had this problem. At 60 mph, it felt like my foot slipped off of the gas pedal for a second.

This happened to me in 1994 (the car is a 93 240 sedan) when the car had about 25K miles on it. The dealer replaced the AMM (the car was under warranty) and the problem has not occurred since (I still have the car).

Kreg

Check for a failed in-tank pump if it does this when the tank is low. It will not cause a no start condition if the in-tank pump has failed, but a sputtering and loss of power when the tank is at about 1/3 and below. It will NOT run at 100%, if it has failed completely (more like 90%), so it may not be the problem. Then again you may not notice that it is slightly down on power.
Charles

Friend,
Good call on the failed in tank fuel pump!
Pulled the pump to learn that the pump was binding.
Thanks for your help,
Jerry

Have you cleaned the throttle body and IAC valve?
--
'92 240 wagon, 285k, '90 240 sedan 229k

Friend,
Both have been cleaned within the past 100 miles.
Thanks,
Jerry

There's a chance the catalytic converter core failed, and road vibration shifts the core to block the outlet.

If you grab the pipe downstream of the cat and shake it side to side (COLD endinge, please) and you hear something loose, that's a sign the cat has failed. Engine vibration on startup will frequently - but not always - shake the loose internals free again.
--
Thank goodness we don't get all the government we pay for. -- Will Rogers

Friend,
Good call on the cat, but no good for this car. I just recently pput a new "Y" pipe on the car, while replacing the pipe, I noticed that someone had previously hollowed out the cat.
Thanks for the help,
Jerry

Probably the fuel pump relay. Always good to change the fuel filter, but draining the tank looking for water in not necessary. The fuel pickup tube is on the bottom of the tank and will suck up any water first.
You have 2 fuel pumps, and if the tank is less than 1/2 full, the secondary pump in the tank may have failed. This pump can be heard faintly by removing the gas cap and listening closely for the faint humm. Usually a no start condition.

Klaus
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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)

Friend,
Good thoughts on the relay and fuel pumps. I replaced the relay with a good relay only to learn that the in-tank pump wasn't working. I order a replacement from Advance Auto and was on the road with in an hour.
PS: also replaced fuel on firewall with new waterproof holder.
Thanks for all your help!
Jerry

Have you checked the air box thermostat lately. Maybe its failed and causing the amm to malfunction before it really goes out on you. If its actually hesitating to the point that it might stall or runs rough that is. Although you describe it just kind of bogging down more than nearly stalling/rough running.