93 4.0 starting issue

[mounties83]

Lately my truck is taking a lot longer to crank over than usual, problemly about a solid 4 seconds, and sometimes i have to crank it again. Any ideas. oh and also have thrown some trouble codes saying its running rich. Fuel regulator?, fuel pump? What do you think? Any help is appreciated.

 

[06RangerXLT]

Bad MAF is gonna probably be your problem. and the downstream o2 is picking up on it. that CAN make it hard to start.

 

[99RangerOffRoad]

I am having the same problem.
Did you ever get it fixed?

 

[daniel3507]

I'm having the same issue so I'll be following this

Sent from my LS670 using Tapatalk

 

[Earl43P]

Try priming the fuel system before cranking the starter.

Turn key to Run (Idiot lights come on in dash, fuel pump runs for 2 seconds).
Turn key back to Off, repeat.

THEN crank the starter.

If that works, your fuel pressure is bleeding down.
That can be a bad checkvalve in the fuel pump, bad fuel pressure regulator, stuck open injector or bad fuel filter or leaky fuel line quick disconnect fitting.

Running rich could be a lot of things, but I would test the IAT and ECT since they have a large input for fuel mixture. MAF would be far down on my list since the ECM ignores most inputs until it warms up and goes into closed loop. I wouldn't expect it to have any effect on a hard to cold start problem.


http://www.oldfuelinjection.com/?p=28
http://www.oldfuelinjection.com/?p=29
http://www.oldfuelinjection.com/?p=64 << Read the Start/Crank and Cold Start/Warmup paragraphs.