[cape99ram]

hi i have 2 misfires in my 99 5.2 v8 on cylinder #2 and #6. both plugs look okay and ive ran a pint of soltron through the fuel system hoping it might clear up gunk in the screens of the injectors... it didnt so i went and bought 2 injectors and id like to replace them now... i was told my my automotive teacher to pull the fuel pump relay and run it till it runs out of fuel in the lines so i can safely pull the fuel line from the rail... all i found was a "fuel system relay" so i pulled it and the truck wouldnt even fire so im assumig that shuts everything down... im wondering where the "fuel pump relay" is and if im actually doing this right. id like to have this done soon because id like to sell the truck. any help would be appreciated and any tips on replacing the injectors. thanks, Grant

 

[ramfam]

I think you have to manualy depressurise system fuel pump relay and asd relay work in conjunction. Fuel pump has to come on when key is turned on and asd relay is active to prime injectors when key is in start or off position.

 

[cape99ram]

any idea on how to depressurize it?

 

[ramfam]

Do you have schrader valve on left fuel rail? Or losen fitting at rail its self. I can't quite remember. Last fuel injector I worked on was a 94 vortec 6 with spyder injector.

 

[ramfam]

The valve is in left fuel rail between 7&8 injectors. And did you try marvel oil in tank of fuel to try to lube up needle valves . Somtimes that helps missfire issues

 

[cape99ram]

hey i used the valve and it depressurized it for the most part. thanks for the advise :smiley_thumbs_up: i got the fuel rail unbolted and pulled one of the injectors to find out autozone gave me the wrong ones:4-angermax::doh: so i put it all back together... i didnt use marvel oil but i used a bottle of soltron in a full tank of gas.... dont know if it helped. is marvel oil any better?

 

[ramfam]

I don't know about better? But a buddy of mine was haveing missfire issues and he didn't want to pull the rail. I can't blame him he and I both have caravans (no thank you).

 

[cape99ram]

I don't know about better? But a buddy of mine was haveing missfire issues and he didn't want to pull the rail. I can't blame him he and I both have caravans (no thank you).

yea pulling the rail sucked... it dented a little bit. everything is easy except pulling the rail