Bronco II problem with first start

[eduardox88]

Hello guys,

I came here to find help from you because my Bronco II 1987 Eddie Bauer is giving me problem in the morning at first start.

When I start in the morning almost always it shuts down after 3 or 4 seconds then on a second start it stays normal. For me seems like is running rich althoug it doesnt smell like that but when I press the accelerator slow the revs goes a little bit down sputtering and then goes up (almost always this condition too).

The video here is for startup condition on the morning.

https://www.youtube.com/watch?v=RQ16VAHXcdU

Any suggestion?

What I have changed:

1-Exterior fuel pump
2-Fuel filter
3-IAC valve
4-Coolant temperature sensor
5-IAT (Intake air temperature)
6-TFI Module
7-ICM Coil
8-Injectors are new
9-Spark plugs
10- Sparks Wires

What do I want to change
1-Fuel pressure regulator

I'll appreciate your help.

Thanks

 

[James H]

If you have access to a fuel pressure guage, put It on and leave it on over night and see if you have and pressure bleed on cold soak.

Sent from my XT1080 using Tapatalk

 

[eduardox88]

Bronco II first start problem

If you have access to a fuel pressure guage, put It on and leave it on over night and see if you have and pressure bleed on cold soak.

Sent from my XT1080 using Tapatalk

Hi, thanks for your answer. Some months ago I used a fuel pressure gauge and the pressure was good but I didn't let it until next day. I don't see any leak in fuel system but will try and update you!

Thanks!

 

[James H]

What you want is for the system to hold pressure, with it long cranking, I'm thinking the check valve is bad and draining the fuel back after it sits too long.

Sent from my XT1080 using Tapatalk

 

[wildbill23c]

The fuel pressure regulator in my 88 Bronco 2 was bad, so after it would sit overnight it would lose pressure causing a no-start on the first time cranking in the morning. It was a slow leak so during the day it would usually start up just fine.

 

[eduardox88]

The fuel pressure regulator in my 88 Bronco 2 was bad, so after it would sit overnight it would lose pressure causing a no-start on the first time cranking in the morning. It was a slow leak so during the day it would usually start up just fine.

I finally check fuel pressure, it's at 40psi switch on engine off, with engine started it's at 34psi. If I disconnect vacuum from FPR the psi goes up to 42 so I think FPR is good, do you?

Also I tried to do a leakage test but I think did something wrong. What I did was:
1- I put switch on, pressure went to 40 psi, turned switch off and after 1 hour psi dropped to 29 so 11 psi in 1 hour. After some time it went to 10psi.
2- loaded pressure again, close return line but after some hours pressure dropped to 5psi
3- loaded pressure and close only incoming fuel line but after some hours pressure went to 5psi.
4- loaded pressure and close both lines but next day was at 5psi again.

I think the hoses were not closed at all :S what do you think?

I'm not sure if the problem could be inyectors. I did 200 miles on Sunday at high speed and after that it has been starting up fine.

The idling is not good, I think all these symptoms are related. The engine hesitate sometimes, if I set idle at 900rpm sometimes it goes lower and compressor start turning on and off but sometimes it remains on normally :S

The scanner only give me code 18 (idm) and 67( Neutral Safety Switch)

I DONT KNOW WHAT MORE TO DO. PLEASE HELP

 

[JerryC]

Have you checked for vacuum leaks?

 

[eduardox88]

Have you checked for vacuum leaks?

Well, I didn't do a vacuum leak test exactly, I just checked my lines and I didn't see broken lines. Lines I checked:
1-FPR line
2-MAP sensor line
3-Brake vacuum line
4-IAC valve line
5- pcv lines (I think these doesn't affect idle)
My bronco is not using other vacuum lines. Those lines are EGR feedback sensor line, the other one that opens the EGR, the vapor canister line and also the Cruise Control vacuum line.

How do you suggest me to do check correct vacuum leak check?

Thanks for your help!

 

[JerryC]

You could use something like carb cleaner or propane.
Propane is safer. The idea is to spray it around the lines and gaskets and listen to a change in the engine.
Mine has had the gasket fail between the lower and upper intake and the grommet at the brake booster.
There's also a way to use a smoke machine.
You should check YouTube for some videos.

 

[eduardox88]

You could use something like carb cleaner or propane.
Propane is safer. The idea is to spray it around the lines and gaskets and listen to a change in the engine.
Mine has had the gasket fail between the lower and upper intake and the grommet at the brake booster.
There's also a way to use a smoke machine.
You should check YouTube for some videos.

Perfect, I will do this on Saturday and update you.
Thanks