2 yrs ago I rebuilt our 1987 760 turbo engine. All good till last month where it started to hessitate, die, or experience lack of power after warming up.
So Far, I have replaced: in tank fuel pump & in tank fuel pump hose. In line fuel pump. Fuel filter, Fuel pump replay, coil, plugs and wires.

Im out of ideas here.

Hi ejray,

Nice job finding the fault and posting back.
Did the bad AMM show any bad resistance measurements between pins?

Did you look at the bad AMM to find a possible bad solder joint or other fault on the AMM circuit board/ connector?

Do an autopsy and maybe repair the bad AMM for a spare, and share what you find.

Bill

So here it is folks,,,, After replacing: in tank fuel pump, in line fuel pump, fuel filter, fuel relay, O2 sensor, Coil, wires and plugs,,,,, we bit the bullet, and replaced the AIR MASS sensor and she runs like a champ again.

WE love this family car and after a complete rebuilding of the engine 2 yrs ago, we weren't willing to toss in the rag...

Thank you for your suggestions SHE LIVES!!

You've replaced a lot, hopefully with new or else used that's known to be good. A bad O2 sensor can affect performance, especially as it warms up, but shouldn't cause it to stall out. I'm wondering about the igntion side. Hopefully it's not the coil, which can get worse as the engine warms. A worn distributor cap/rotor can make for misfiring and a stumbling hesitation leading to stalls and no-starts. Your B230FT uses a Hall sensor in the base of the side mounted distributor to detect rpm for timing, which can make for problems when it starts to fail before becoming a no-start. If this started getting noticeably worse after installing the pre-pump, any chance you got the wiring reversed? The black wire on the pump isn't always ground. The pump doesn't run in reverse, but I believe it causes flow resistance when wired backwards. You can idle okay, even rev it in neutral, but there can fuel starvation at increasing rpm under load. It once happened to me wiring it backwards (I actually knew better, just wasn't thinking that day).
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

Add the check for the Turbo air induction intake piping for air intake leaks?

To the 700-900 Series FAQ!:
https://www.brickboard.com/FAQ/700-900/EngineTurbo.htm

Never owned a Turbo.
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