Hard start / long crank to start issue SOLVED

91AOD5.0LX

I have a slight sag in my rear
Feb 20, 2021
252
127
53
North East
I post this in hopes of helping others that may be experiencing the same problem:

Car:
1991 LX 5.0 Stock

Problem:
Car cranks for about 7-10 seconds before it finally starts then runs fine

Note:
Car always runs perfect after it finally starts. No acceleration or idle issue. Never stalls and fuel pump can be heard priming normally for 3 seconds before starting. The long cranking issue always occurs. It doesn’t matter if the motor is cold or warm. No codes popped and fuel pressure seemed fine.

Solved:
Fuel pump was bad. Replaced and starts like new now. Old fuel pump had a crack in it.

** I wanted to share this with others who may be experiencing a hard start problem because there is a long list of fuel/spark parts that can be causing this problem, some of which can be eliminated due to other factors. While discussing this off-line with others, I was told to eliminate the fuel pump as the cause because it either works or it doesn’t and even if it’s defective and it’s still working for some reason, that the car would run like crap, etc. In theory that makes perfect sense but I went ahead and swapped out a new pump and she starts like new now and runs like a beauty. Therefore if your experiencing a long starting issue but your car still runs fine once it’s started keep in mind that although it can be something else causing the problem that the fuel pump may actually still be the cause and shouldn’t be eliminated from the list of possibilities because the car runs fine and no codes are pushed out, etc.
 
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Wayne Waldrep

Before I post a pic, do you have one of yours?
15 Year Member
Apr 14, 2003
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Cuba, AL
You described what's going on with mine exactly. I haven't wanted to post yet because of the same things I've heard about the fuel pump. It can't be that because it either works or doesn't. There's also the electronics in the distributor which are a crap shoot to find decent replacements for. Then you have the capacitors in the EEC. I just replaced those. There's 3 of them. One of mine was not even connected...just laying there. One only had one leg. The other was still connected right but was leaking some. I just knew that would solve the starting issue. I mean, how could only 1 out of 3 even connected not do something right? Nope. Had absolutely zero effect on anything. After that I swapped distributors to a spare OEM one I have. Also zero effect. My fuel pump is one I put in about 25-30 years ago. It is a 155lph that came in my Powerdyne supercharger kit. So it's lasted forever! Maybe I'll just swap that just to see if I might have one bit of good luck like you did. Doubtful for me though. My last bit of good luck was when I was in the 5th grade.
 

91AOD5.0LX

I have a slight sag in my rear
Feb 20, 2021
252
127
53
North East
You described what's going on with mine exactly. I haven't wanted to post yet because of the same things I've heard about the fuel pump. It can't be that because it either works or doesn't. There's also the electronics in the distributor which are a crap shoot to find decent replacements for. Then you have the capacitors in the EEC. I just replaced those. There's 3 of them. One of mine was not even connected...just laying there. One only had one leg. The other was still connected right but was leaking some. I just knew that would solve the starting issue. I mean, how could only 1 out of 3 even connected not do something right? Nope. Had absolutely zero effect on anything. After that I swapped distributors to a spare OEM one I have. Also zero effect. My fuel pump is one I put in about 25-30 years ago. It is a 155lph that came in my Powerdyne supercharger kit. So it's lasted forever! Maybe I'll just swap that just to see if I might have one bit of good luck like you did. Doubtful for me though. My last bit of good luck was when I was in the 5th grade.
Keep me posted if it was your fuel pump or not.
This is exactly why I posted this. I Hope this solves your problem. There are so many parts that can cause this on the spark and fuel side. I wanted to let others know that sometimes the part you eliminate such as the fuel pump because you would expect other symptoms which you don’t have might actually be the problem. I waited months before deciding to change it because although I had a feeling that may be the problem I also felt at the same time that it didn’t make sense because once started the car was fine. I finally decided to try it and now kick myself for not doing it a long time ago. Everything you Mentioned about the distributor, electronics and computer was on my mind as well and was thinking that’s more likely than the fuel pump. I also looked at the fuel pressure regulator, the fuel vapor selenoid, ignition module, bad grounds, MAF, etc etc etc.
Try swapping out the pump and let me know how that goes. You may be pleasantly surprised as I was.
 

Wayne Waldrep

Before I post a pic, do you have one of yours?
15 Year Member
Apr 14, 2003
1,148
621
143
55
Cuba, AL
Will do. Thanks for posting your info. Just for others reading this that drive a fox, even if you're having no issues I think you should replace the capacitors now before the leakage ruins the circuit board. They are literally 20 cents apiece.