--brickboarders--

Left the '87 240 for a couple of weeks while on a trip in the , came back, started up just fine, took my daughter to swimming... Went to pick her up a couple of hours later, car started but suddenly wouldn't idle, at all. I think it was mad at me, probably jealous of its Japanese rival. Couldn't drive it. Really had to keep my foot in it just to keep it alive. Dies as soon as you stop pumping the gas pedal. Ran fine a couple of hours ago, and for years before that! Only problem in recent history was mass meter died a couple of months ago so I checked the new one for possible infant mortality: resistance btwn pins 2 and 3 is right on. Think it must be something else. Your thoughts would be _very much_ appreciated! Thanks in advance.

Kevin

Many thanks to all who responded! I did unplug the AMM, started it up and, sure enough, it idles fine. So we know the AMM is the culprit. When the first AMM failed, a couple of months ago, I replaced it with one salvaged from a wrecked 87 240. The airbox thermostat was bad, so I disconnected the warm air hose thereby ensuring, I thought, that any air entering the airbox would be cold. Now that the second (salvage) AMM has also failed, I'm wondering if it is just coincidence, or if there is an underlying common cause between the two failures...

I understand there is a feature that applies high voltage to the wire in the AMM to burn off residuals when you turn off the engine. Perhaps this feature has failed, leaving residuals on the wire that build up and, ultimately, result in AMM failure? Here's yet another interesting point: When I bench tested the first failed AMM by turning the adjusting screw while measuring the resistance, it was within spec and seemed to work just fine. So today I put that AMM back in, just to see if it would work. It did, the car drove fine...for two blocks! Could the residuals have fallen off while I was bench testing it, and then built right back up again after two blocks of driving? It seems unlikely...

Primary concern now is investing in another AMM, only to ultimately lose my investment because I haven't yet discovered the root cause of two AMM failures in close proximity to each other.

re; "...took my daughter to swimming.... Only problem in recent history was mass meter died a couple of months ago ...."

Recurrence of the same problem? Did you replace the AMM with a new one, or a used one?
And obviously, it must already be warm where you are (viz., your daughter's swim), so did you check your air filter box to see whether its thermostat is working properly. If its stuck on the "heat" mode, you just cooked your second AMM.

Personally, I don't trust that thermostat -- I rip them out of the air filter boxes of all my cars, and seal the "heat tube" opening so they're always drawing colder air -- all for the sake of protecting my AMM.

I'd do the AMM diagnostic again -- disconnect (with the key off) and then try to see if the car idles.

Good luck.

Come on guys, his AMM died. Classic. Unplug the air mass meter and start it up. It should idle fine, which confirms the AMM. It will not be operable but now all you have to do is get a used 007 AMM for $100 or less.

Kevin,

When is the last time you cleaned the throttle body? If it gets gummed up, it won't shut all the way and trigger the idle switch.

Other thought is a vac leak. Check all the vac lines for leaks. Good luck!

-Josh

When it was sitting was the gas tank full? If not it could have water in the gas tank. Before you start checking anything go to the auto parts store and buy two cans of dry gas. Put it in the tank and if you can get it running long enough take it for a long ride on the highway. If this doesn't help then my guess is a vaccume leak or fuel injection problem...

Best of luck...
--
Volvos4me4ever 1989 245 274K miles still going strong, 1992 745 Turbo 110K miles real nice!

--brickboarders--

Left the '87 240 for a couple of weeks while on a trip in the (Toyota), came back, started up just fine, took my daughter to swimming... Went to pick her up a couple of hours later, car started but suddenly wouldn't idle, at all. I think it was mad at me, probably jealous of its Japanese rival. Couldn't drive it. Really had to keep my foot in it just to keep it alive. Dies as soon as you stop pumping the gas pedal. Ran fine a couple of hours ago, and for years before that! Only problem in recent history was mass meter died a couple of months ago so I checked the new one for possible infant mortality: resistance btwn pins 2 and 3 is right on. Think it must be something else. Your thoughts would be _very much_ appreciated! Thanks in advance.

Kevin