CAW
Member
- Joined
- Aug 12, 2007
- Messages
- 14
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I have been having some trouble codes in cold weather p0171 and p0174. I know these codes are indicative of a lean condition. I decided to do some troubleshooting to find any possible vacuum leaks. So I built a smoke leak test machine out of a paint can, a glow plug and an air compressor. It works pretty well. There was smoke from the egr valve and the IAC valve. I got a new IAC valve and replaced the old one. I did another smoke test to see if there were anymore leaks. However, smoke poured out of the iac valves vent/breather/ cap. I did some internet research and found a few forum posts that said smoke from the IAC vent was normal during a pressurized smoke test. There were also several forum posts that said any escaping smoke indicated a vacuum leak and a defective valve. I have no idea what to believe. What do you guys think?
I made sure that I didn't over pressurize the intake components and damage them. the air compressor regulator was set as low as I could get it and still have any flow, only a couple psi. The new iac is a BWD brand. 1997 4.0 OHV engine.
I made sure that I didn't over pressurize the intake components and damage them. the air compressor regulator was set as low as I could get it and still have any flow, only a couple psi. The new iac is a BWD brand. 1997 4.0 OHV engine.