Random long cranking hard to start problem

[812EnRoute]

My 2000 5.3 Tahoe has started to have a random long cranking almost wanting it to not start problem. It started happening a week or two ago. At first it was maybe once every 10 starts then got to be a little more frequent but then it will be ok for a little while. One of my buddies suggested EGR but then after hearing it he said probably not. I figured it was with the fuel and another buddy agreed with me. Possible fuel filter and or maybe shortly needing the pump (and if it is he already knows he is gonna be helping with it.) I've tried looking for the specs on the fuel pressure and have found no real good help. Anybody know what the specs are for the fuel pressure? It started to bug me tonight because I have so much going on right now with the house and all that I put the gauge on and took some readings at 11:45 at night. Off course as we all might know, with me looking at it with a gauge it ran fine and had no problems any of the 20 some times I started it.
The readings I got
Key on Engine off ~ 50 psi
Cranking ~ 56 psi
Running ~ 48 psi
Truck off after running ~ 45 psi

 

[ZX1100F1]

The Key-On Engine-Off pressures should be 48-54

Dirty fuel injectors can cause hard starting conditions.
I would also recommend replacing the fuel filter and also check and/or replace the fuel pressure regulator.

How many miles on the engine?

 

[812EnRoute]

Truck has 91647 miles on her got her around Thanksgiving of 07 with around 85000 I think. I was told it had regular maint done on her. Looking at the car fax report there has been a lot of work done on her at the dealership but who knows if it was only warranty work or if it shows other work that has been done at a dealership can't remember. I'll have to find it and see. Oh one more monkey wrench to throw into the whole thing is she has an after market remote start on her. She has been good the past few days but when I hit the remote start a little while ago it acted up. Thinking now it might be more electronic maybe? Possible remote start acting up?

 

[puckhead]

Mine has also started having this problem. Nothing major yet I just notice it takes a tiny bit longer to turn over. I recently replaced my fuel filter so I dont think thats it. If it is dirty fuel injectors, can you clean them or do you just have to replace them? Thanks!

 

[ZX1100F1]

I have seen after-market remote start kits introduce all sorts of problems, but with that amount of miles I would suspect dirty injectors still.

The easiest way to clean the fuel injectors yourself is to add four to six 12oz bottles of Techron fuel system cleaner to one full tank of gas and drive the entire tank out, you can pick up a 6-pack of Techron at Costco or Sam's Club for about $15.

 

[812EnRoute]

I have seen after-market remote start kits introduce all sorts of problems,

That was one of the things I did not really care for when I bought the truck because I have worked on a lot of problem cars that have been not working correctly due to remote starts. Most of them have been at a Toyota Dealer and it seemed like for me working there "after market" is bad, "stock" is good. Then I went to a Chevy dealer for a little bit and there thing was stock good and after market a bit better until something went bad and after market had to be the problem. Now its what ever works and works good as long as I know how and why. But I figured that it had it in it all ready and no problems yet so it should be working good. I got the fuel filter today and hopefully get time to put it in soon.

 

[jm58]

I have seen after-market remote start kits introduce all sorts of problems, but with that amount of miles I would suspect dirty injectors still.

The easiest way to clean the fuel injectors yourself is to add four to six 12oz bottles of Techron fuel system cleaner to one full tank of gas and drive the entire tank out, you can pick up a 6-pack of Techron at Costco or Sam's Club for about $15.

4-6 bottles in one tank?

 

[lgjohn]

Problem solved

My 2001 LT 5.3L did the exact thing. At first I thought it was the fuel pump going out, having 100k miles on it. After replacing the pump, it didn't fix the problem. I started looking at the fuel pressure regulator. It is on the fuel rail on the intake manifold on the driver side. I pulled the vacume hose off of the regulator and fuel came out of the hose. That was the indicator that the regulator was bad. I replace it with a new one and it starts like new. It takes about 5 minutes to do. Hope this helps you. Good luck.

 

[812EnRoute]

My 2001 LT 5.3L did the exact thing. At first I thought it was the fuel pump going out, having 100k miles on it. After replacing the pump, it didn't fix the problem. I started looking at the fuel pressure regulator. It is on the fuel rail on the intake manifold on the driver side. I pulled the vacume hose off of the regulator and fuel came out of the hose. That was the indicator that the regulator was bad. I replace it with a new one and it starts like new. It takes about 5 minutes to do. Hope this helps you. Good luck.

Thank you I will have to try that. I'll let you know what happens. Been a little busy lately. Gutting the basement last week. This weekend I made made many trips to the hospital for my grandfather and I did the roof on the garage this weekend. Fiance and I striped it off while dad threw in dumpster, and my brother and I roofed it today. About a 675 sq ft roof and about a 528 sq ft garage. Now I'll have the garage done to work on the truck and mustang and every other toy I get my hands on between me, my brother, and friends.

 

[812EnRoute]

just checked the regulator line a little bit ago to see if there was gas in it and sure enough there was. Hopefully I will have time tomorrow to replace it. Once I do replace it I'll let you know how it is.

 

[812EnRoute]

Put the regulator in about a week ago and have had to abnormal starting since then. Thanks lgjohn for the heads up on the regulator. Things have been so busy lately and with out the garage being done, trying to work on the truck has been to a very minimum.

 

[lgjohn]

Your welcome, Glad I could help.

 

[98-New 2door]

That worked for me, thanks for the help. Had long cranking periodically and even almost stalling at idle. Threw 2 12 oz bottles of the Techron fuel system cleaner mentioned above and it's been a champ ever since. I mixed it every 6 gallons then topped it off.

 

[jonjon1040]

is the fuel regulator in the same spot on an 07 tahoe ltz also with a 5.3l engine?

 

[84jeepjohn]

Crap. I'm having the same issue but on an 05 burb with the 5.3. Looks like mine is part of the sending unit?

 

[Baldgoat]

I have a 2000 Tahoe doing the same thing. My regulator vacuum line does not have fuel in it. Throwing a p0138 code & a p0446 code. 446 code is the evap. I replaced the fuel vent solenoid & it cleared for about a month. Idles fine, drives fine, never stalls. Are the 2 tied together. Maybe one causing the other?? Any help would be appreciated.

 

[TropicalBob]

2003 5.3 Flex Long Cranking before start

I have an 03, Flex fuel 5.3. ( 296K miles )
I had a Pressure Reg Failure and replaced it. Then the Throttle Position Sensor ( TPS ) had to be replaced.
Now it cranks for 20-30 seconds prior to starting.
I cut an access hole in the floor and replaced the Fuel Pump Assy today,
easy job, DO NOT drop the tank, that's just to difficult. Cut the access hole.
contact me for measurements, procedure.

Anyway, to my question. Why is this vehicle cranking so long prior to starting?