Cursed or what?

[robic58]

I have a 1989 Mercury Grand Marquiswith @ 80,000 miles on it, the body is superb, the undercarriage rust free,
has a smoth running 302, a strong AOD tranny, paint looks good,and interior is comfortable, brakes and steering are excellent
.................so...what do I have to complain about......
at the moment three issues- a no crank-no start issue but only with outdoor ambient temperature at freezing or below.. if mild, starts just fine
, but if it's cold out no go... and not the battery... it is excellent,..... but it's an electrical issue I can not diagnose.
second issue-- when it does start- it does very nicely, but in any gear... suspected the AOD mounted neutral safety switch...
replaced it with a new one.. no difference, starts in any gear.. and that's a hazardous proposition.
third issue--- minimal interior heat.... replaced heater core... no diffreence.... replaced thermostat with new 195* -- no
different....
so . H .E L .P ... please..
Any and all advice will be appreciated. Thanks, Ralph

[dmccaig]

Dear OP>

Does it fail t start in the morning after a long run the night before?

Donald

[Tiggie]

Problem 1 and 2 may be related. Someone has bypassed the neutral safety switch - look for wire hacking - specifically a jumper wire. If you unplug the NSS, does it still start? It shouldn't.

On the cold no crank, need to check to see if starter is getting ~12V and has a good ground. If that checks out okay, starter is suspect. Otherwise, do the same to the starter solenoid on your passenger side fender. Any clicking when turning they key on the no start condition?

3rd issue - if the engine is warm and still no heat, it's usually a blend door issue. Does your car have automatic climate control?

[gadget73]

Is it automatic climate control? If so, check here:

http://www.grandmarq.net/vb/showthre...lems-Read-This!

Have you ever scanned it for codes? A bad air or coolant temperature sensor can cause starting issues in cold weather. It may or may not throw a code, but thats the first place to check. Failing that, you may have to poke at the sensors and read them directly with a meter

http://www.grandmarq.net/oldfuelinjection/page10.html

Agree that someone probably jumped out the NSS switch. The connector that feeds that harness hangs behind the back of the engine. Look for fuckery in that area, sometimes the connector gets crusty and it won't crank. I can completely imagine someone wire-nutting the circuit together rather than just cleaning the plugs. You might also look for non-stock looking wiring connected to the small terminal on the starter relay. If something has been bodged in there, trace it and see what its hooked too.

[robic58]

Thanks toall= a few more things for me to check out.. will post findings

Is it automatic climate control? If so, check here:

http://www.grandmarq.net/vb/showthre...lems-Read-This!

Have you ever scanned it for codes? A bad air or coolant temperature sensor can cause starting issues in cold weather. It may or may not throw a code, but thats the first place to check. Failing that, you may have to poke at the sensors and read them directly with a meter

http://www.grandmarq.net/oldfuelinjection/page10.html

Agree that someone probably jumped out the NSS switch. The connector that feeds that harness hangs behind the back of the engine. Look for fuckery in that area, sometimes the connector gets crusty and it won't crank. I can completely imagine someone wire-nutting the circuit together rather than just cleaning the plugs. You might also look for non-stock looking wiring connected to the small terminal on the starter relay. If something has been bodged in there, trace it and see what its hooked too.

I'll follow up on recommendations- will post findings. Thanks again

[robic58]

Update, Jan 25/17... Being in the semi frozen North, not everyday is conducive to work on old steel.
However success in one area... Replaced the starter solenoid with one from "rock auto". And now starts every time.
One gremlin down!
Also replace the "neutral safety switch"... Made no difference.. Still starts in any gear.. To take it one step further disconnected the "nss" wiring from the switch... And ... Still starts in any gear. So, obviously something in the starting circuit is by-passing the "nss". Given the season, I think I'll leave the critter until we get better/ warmer weather.
Again, thanks guys. Ralph

[79lincolnlover]

Did you lose power last week?

[ralph.robichaud]

Did you lose power last week?

Only for a day, we were lucky.. It would wear pretty thin after the second day!
Thankfully , the temperatures were reasonably moderate.

How about you? How did you fare?


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