P0102 and P0306

[fyredude57]

I have a 1996 5.7 with a mass air flow circuit low input and a miss fire on cylinder #6. New plugs wires cap and rotor or "plug" fuel pressure is steady at 65psi it has the dreaded spider injectors....
Should I replace the mass air flow sensor.... Or could the low input be due to the misfire??? My first step is to run GM injector cleaner through the system to try and get rid of the miss fire?? I am at a loss Please help Thanks... Truck still runs fine but i am **** and like it to be right.. 96 5.7 with 103,000 miles.

 

[LI99HOE]

When I had the P0306 I Seafoamed the intake using the spray type, and followed the directions to the point. Got rid of the misfire for me.
As far as the the mass airflow.... pick up some mass airflow cleaner(specifically), take off the unit, clean, and reinstall.
Hopefully this will help ya'.

 

[SunlitComet]

my original spider assembly caused misfires on 5 and 7 and effectively the p0102 went away once the spider was replaced. clean the maf afterwards.

---------- Post added at 05:08 PM ---------- Previous post was at 05:06 PM ----------

just replace the spider, cleaning is not always effective.

 

[LI99HOE]

[/QUOTE]just replace the spider, cleaning is not always effective.[/QUOTE]

Very true, but will save him sum $$$ if it does.
Like Jonathan says... it doesn't ALWAYS work.... but it a cheap start.

On an afterthought look at the spark plugs under the hood @ night while the truck is running. Make sure there's no arcing from the plug/wire boot connection to the bottom of the plugs(ground section), or engine. Sometimes not enough Dielectric grease will result in arcing, and hence misfires.

 

[fyredude57]

Gonna try cleaning first. No arc at night checked that. I have had a 95 5.7 that i Sea foamed and 100 miles after i had to replace 4 O2 sensors.... I beleive GM makes a cleaner that is O2 sensor friendly.. Although the Sea foam worked very well I just plan on having to replace the O2 sensors. I appreciate the help and will update tomorrow when i have tried to clean...
I cant seem to give up theese 5.7's and the same problems occur. I have had 4 now and still love them.

 

[fyredude57]

New Mass Air Flow Sensor, Seafoamed......Idles better no codes yet we will see. Lots of smoke 30 minutes to clear