Fuel Pressure LeakDown test

H

hotstang

Founding Member

May 18, 1999

602

0

17

Tennessee

Apr 16, 2012

#1

• Apr 16, 2012

• #1

I am trying to diagnose my 2002 GT. It is basically stock but has 114K on the odometer. When I start it first time in the morning it smokes like a freight train but is fine after that. The smoke is white but does not smell sweet like Antifreeze and is not using oil.

No oil in Radiator

No Water in Oil.

Not using any oil

Not losing any antifreeze.

My only thought is maybe an injector is leaking down and causing it to smoke in the morning. It will run rough for a few seconds then is fine.

What is an acceptable amount of leak down in the fuel system? 5LB a minute? 10? 1? none?

Thanks

 

wmburns

SN Certified Technician

Aug 14, 2009

5,892

514

204

Houston Texas

Apr 16, 2012

#2

• Apr 16, 2012

• #2

Pinpoint test H58 (fast leak down) is no more than 5 PSI after 10 seconds.

Long term, the fuel pressure should be within 5 PSI after 1 minute.

If you suspect an injector problem, consider an injector cleaning/flow test service such as InjectorRX.com. Once cleaned and flow tested, the injectors are as good as new. Cheaper than new.

 

Z

z28forlife

New Member

Sep 12, 2005

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0

2

Apr 16, 2012

#3

• Apr 16, 2012

• #3

If the injector is leaking it would probably be leaking all the time, not just after the car sits. White smoke is usually antifreeze and blue is oil. How long has it been doing it?

 

H

hotstang

Founding Member

May 18, 1999

602

0

17

Tennessee

Apr 18, 2012

#4

• Apr 18, 2012

• #4

Thank you for the replies..... I jsut bought the car about a month ago and it never did it when hot until I flushed the coolant and did a pressure test at 17PSI. Here is where I am now

I noticed some white smoke coming out of the tailpipe so I decided to do a Blcok Test and Compression test. I ran the block test with the car at normal operating temp and the fluid went from Sky Blue to Clear (not yellow not green). When I ran the compression test with the TB Wide open here is what I got
1. 190
2. 172
3. 177
4. 184
5. 170
6. 177
7. 190
8. 192
The numbers look good to me, I know a 22 point difference is high but they are all above the Ford "140" minimum I am hearing. I can also look in the plug ports and see the cross hatch still in the cylinder walls so that is good......

I had the radiator cap off and ran the compression test and noticed when running it on 1 and 6 that the coolant level would rise to overflow just a bit. So with the results I am thinking I have two blown head gaskets????? That does not seem likely to me but what do I know......
Your thoughts? How much does a machine shop usually charge for plaining and a valve job now?
Thank you

 

wmburns

SN Certified Technician

Aug 14, 2009

5,892

514

204

Houston Texas

Apr 18, 2012

#5

• Apr 18, 2012

• #5

Bubbles in the coolant during a pressure leak down test does point to a blown head gasket. It could also explain the other symptoms.

There is a test strip for combustion by products in the coolant. A positive test would tend to confirm the diagnosis.

 

H

hotstang

Founding Member

May 18, 1999

602

0

17

Tennessee

Apr 18, 2012

#6

• Apr 18, 2012

• #6

Thank you alteady got the intake off this is going to be fun.