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sprinkles08, Chrysler/Dodge/Jeep master tech
Category: Dodge
Satisfied Customers: 22985
Experience:  ASE Master and Advanced Certified, Chrysler/Dodge/Jeep Master Certified, Trans and Hybrid Specialist
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It's Rolland again... the one with the new 2009 Hemi VVT

Customer Question

Hi Tom, it's Rolland again... the one with the new 2009 Hemi VVT from a salvage vehicle in a 1968 Dodge D-100 pickup. Your prior answer lead to no result in repair. I have must in diag and too much to type. The vehicle starts and within a couple seconds goes full rich and slows down with too much fuel until it stalls. Spark plugs are coal black. This issue has been going on in another shop for 5 years. The engine only has five miles on it. Compression is 220 pounds. Fuel pressure is 58-60 pounds and holds with no bleed off. New MAP sensor. No vacuum leaks found. Removed intake and checked it and taped it up and ran vacuum test on it. Removed timing cover and marks are in proper alignment. I know I can't see the VVT system. I know the VVT cam defaults advanced which should increase vacuum at idle. I've plugged the PVC and brake booster for test and no help. What's causing the full rich upon start and won't lean? I can use a Mity-vac hand pump on the MAP sensor to trick it to help lean. As richness develops, the rough run starts and vacuum drops and makes the PCM want to rich en.
Submitted: 2 years ago.
Category: Dodge
Expert:  sprinkles08 replied 2 years ago.

Hello and welcome to JustAnswer!

I have to wonder if vacuum is dropping off after start because of an exhaust restriction. You're using the PCM and all wiring including oxygen sensors and catalytic converters?

Are any fault codes setting?

Does the MAP signal on a scan tool agree with what a vacuum gauge shows?