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Posted by: tdgray May 7 2006, 02:40 PM

Ok so here it is.

Replaced the fuel pump with an MSD (sorry Jake).

Fuel pressure regulator is almost set as high as it will go. Tried multiple settings no change.

Visually looked at the spray pattern of the fuel injectors. Basically a straight squirt. definitely not a mist which is what I expected. Is this right?

The engine sounds as if it wants to start when I crank it. If I squirt some fuel down the throttle body it fires right up (and races like hell of course). So it's not a timing etc problem

Are the injectors bad? Am I not getting enough pressure from the MSD pump? I tried to build a homemade pressure regulator but it does not seem to work very well.

Can an injector go bad but still spit some fuel? What is the pattern supposed to look like? Should I just bite the bullit and get four new injectors just to be safe?

HELP TOTALLY CONFUSED

Posted by: Dr Evil May 7 2006, 02:51 PM

Hey man, the pintle (sp) in the tip of the injector nozzle is what assists the dispersment of the fuel (makes it atomize). If you have the pressure it should work. The only way I can see your injector goofing up is if it is stuck way open, or if there is something in there plugging flow thus causing the pressure drop. There is a filter in the injector itself, IIRC. I have heard from many people that you can simply get an ultrasonic jewelry cleaner from harbor freight and stick them in there over night with some solven. This should break up and clean out any crap that may be in the injector.


BUT!, before going all out you should get a fuel gauge and make sure that you are getting the pressure that you need.
If your engine runs when given fuel from the TB and not from drooly injectors you definetly have a problem in where you are looking. Probably fuel drool from the injectors due to one of the above things.

Posted by: tdgray May 7 2006, 05:40 PM

Thanks Doc...

Got a in-line fuel pressure gauge on order from Jegs as we speak.

I am getting the thought that the MSD fuelpump is not cutting it. Will verify when the gauge gets here.

Just for confirmation... I should install the guage between the regualtor and the fuel rail correct????

Thanks guys..as usual

Posted by: Bartlett 914 May 7 2006, 06:00 PM

The pressure gage should be inserted between the injectors on the passenger side. There should be a port that is capped off. On the drivers side this port feeds the cold start injector. I made my own fuel pressure gage. I purchased a gage from McMaster Carr pretty cheap. It is glycerine filled and goes to 60 PSI. Added some fuel line and I was done.

Posted by: tdgray May 8 2006, 07:02 AM

I have a 1.7 so I have no hose from the fuel rail to the cold start valve.

Question... what size is the port on the fuel rail. I ordered a pressure gauge with a 1/8" connection.

If I cannot fit the pressure gauge on the fuel rail where else can I put it in-line. Tried doing a search but just got more confused.

Posted by: tdgray May 8 2006, 09:26 AM

Another thought...

Could the TPS be bad. Would this cause a no start condition. I'm thinking if it is bad it cannot sense when the throttle is closed.

Maybe I am going in too many directions at once.

Posted by: tdgray May 8 2006, 06:04 PM

for left coast reaction