Hard Start after Fuel Pump replacement

[JPrende]

Hi,

I purchased a 2000 Explorer Sport a little over a month ago. A week ago, the fuel pump died. Had it towed to my mechanic and he replaced the pump. After 3 days, it started to have trouble starting. First I would just quickly turn the key as I normally do, but it didn't start so cranked again and starts right up. It has been getting worse to the point I would have to crank 3-4 times for it to start. Now I have been turning the key to on for a few seconds then turning it off w/o cranking, repeating this a few times to build up pressure. Then it starts right up. The check engine light came on last night as it sluggishly went up a hill. I had the codes run and got P0171 and P0174. The print out states that if both codes come up, to suspect fuel pressure. Could this be a bad fuel pump? Is there anything I should check before calling the mechanic about a bad fuel pump?

Thanks for your help

 

[crunchie_frog]

Could be the wrong fuel pp as well. It could also be leaking at the fuel pump lines in the tank, could have a faulty regulator, or could have a plugged fuel filter. The mechanic can check the fuel pressure at the fuel rail and it should be around 65-70 psig if my memory is correct.

 

[JPrende]

Took it to the mechanic, he thinks the MAF needs to be replaced. Find it odd that this happens 3 days after they replaced the fuel pump.

 

[crunchie_frog]

Did he bother to check the fuel pressure?

 

[JPrende]

Did he bother to check the fuel pressure?

He said that the fuel pressure was fine. I didn't ask what the pressure was.

 

[JusTheUsual]

Mine does this too. New plugs always fixes the problem. I'm sick of the autolite platinums being replaced all the time so I just tried NGK platinums the other day.

 

[JPrende]

The mechanic said it is definitely the MAF sensor. I find it very hard to believe that it fails 2 days after leaving the shop. It will be $200 to fix. But if I don't fix it, he wants to charge me $200 for diagnostics.

 

[Vic_Ferrari2002]

So either way he wants to fleece you for $200. Even if hes right me thinks its time to find a new mechanic.

 

[crunchie_frog]

Ask him if he will guarantee that the replacement Maf fixes your problem?

 

[JPrende]

So either way he wants to fleece you for $200. Even if hes right me thinks its time to find a new mechanic.

Yeah, I am definitely looking into taking it elsewhere from now on. I have been taking my car there for over 8 years. Ever since he hired another mechanic, more thing seem to go wrong, and the bill seems higher.

 

[JPrende]

Ask him if he will guarantee that the replacement Maf fixes your problem?

Well, he did say that it was definitely the MAF. He also said that the MAF needs to be replaced...in his experience cleaning doesn't work.

 

[bill06447]

Sounds like a bad pump, or sucking air from a bad fuel connection (if s/he just replaced the pump and not the whole unit). You will need 30psi fuel pressure minimum at all times, I'd bet it shows 35+ at start up but gradually decreases...

Bill

 

[crunchie_frog]

Fuel pump spec is 65+/- 8 psig.

 

[Flash]

It really sounds like the fuel pump or something else associated that effects the fuel pressure as well as a check valve.

If he can guarantee the MAF will fix it in writing, go ahead.
And tell him if it doesn't fix it he has to fix the fuel problem.

 

[Flash]

Mine does this too. New plugs always fixes the problem. I'm sick of the autolite platinums being replaced all the time so I just tried NGK platinums the other day.

NGK Iridiums.

 

[JPrende]

Well, picked up the truck last night after he replaced the MAF. It started right up. I went out later and it started fine again. But the third start it didn't fire up on the first try, had to crank a second time. This morning it took an extra long crank before it fired up. After I got to work, let it sit for over an hour, then went out to give it a crank. It took 3 cranks to start. This is exactly what was happening last time after I got the truck back from him. Last time I got about 10 starts out of it before it started acting goofy. Now it's acting up on the third time I start it. (and fourth and fifth time too)

 

[Flash]

Are you still getting codes?

 

[crunchie_frog]

Well, he did say that it was definitely the MAF. He also said that the MAF needs to be replaced...in his experience cleaning doesn't work.

Guess you have a nice new Maf. Wonder what he says now?

 

[JPrende]

Are you still getting codes?

The CEL is off. only drove about 20 miles so far.

 

[96EXXLTinCO]

You need to find a mechanic that can diagnose and not just throw parts at a problem until something sticks. There is plenty of members here that will attest to cleaning MAF, and that it works. There is a thread here somewhere as well that describes how to test it. Spend some time searching on here, there is years and years of experience, someone has had the same issue and reported on it I'm sure, just takes a while to find sometimes. Regardless, you will find things you can easily check yourself.