I dropped a SEFI, 5.0L from an '86 Lincoln MkVII into my '53 Mercury M1oo.

It starts no problem ... however, once it's warmed up she's takiin to stalling... particular in intersections and when my 12 year old daughter is on board! [Too much xy]

I've replaced the TFI twice! , and found a poor conncetion as well
and repaired them but the truck is still stalling out when I, come to a stop...not consistently, just annoyingly frequent!

Any suggestions?

GW

 

I don't know what your "TFI" is but I would replace the throttle position sensor. It tends to get worn out in the idle position since it spends a lot of time there. The symptom is engines won't idle well, the rev when you aren't touching the gas or the stall at idle but run fine if you give them a little gas to get them off idle. I be you could swap one in and try it and return it if it doesn't solve the problem.

 

Thanks Boilerbots

I jsut came in from talkin' to my neighbour and told him about the only thing I haven't tried is the TPI so better do that!

Must be a sign, must be sign from the effie gods/dogs

GW

 

I've been camping with the family the past 4 days in the Muskokas.

I was dissappointed I couldn't take the truck but it just isn't dependable enough yet for family travel

ANyways, I'm going ou to the garage later tonight or tomorrow and wondered if any of you gearheads had any other suggestions or a protocol for tracking down this nasty varmit of a problem

LMK

GW

 

I guess a little bit more of a dianosis might help. When it quits running does it seem like the ignition is failing or there is a lack of fuel. You probably need to help narrow down the possibilities since we are just guessing right now.

 

You know, I've been wondering that myself. The fuel pump is cylcing, the tank has gas. There is spark, although that doesn't seem as strong an arc as I would expect, however, I'm not very experienced with diagnosing or recognizing these problems...it's been almost 8 years building this truck, and only 10 months with a running engine

GW

 

Does the 86 have a MAP sensor (Manifold Absolute Pressure)? The 89 from an F-150 that I'm running has one and without it, it stalled constantly. It is located at the passenger firewall near or on the A/C heater box. It has a very large vacuum line going to it from the intake manifold.

Its purpose is to tell the computer that the A/C compressor cycled on or the brakes were pressed or the power steering was turned so it could compensate by increasing engine RPM thus raising the vacuum up to a desired leval.