so my check engine light came on i plug in my diablo tuner it came with the pro charger kit the code that came up is po171&po174 i check my air intake it seem to be tight.does anybody know what it could be thanks
Check Engine Light On
- Thread starter Gabestang
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Look for something that can affect both sides of the engine causing it to run lean with those codes. Most likely it's related to the mods you've done if the codes weren't there previously. A vacuum leak, any source of air entering the engine that's not going through the MAF sensor, a bad MAF sensor itself, a MAF sensor not calibrated for any induction system mods that have been done, low fuel pressure, contaminated gas would all be things to look for to start with.
If you can look at PID's with your scan tool, look at the fuel trims at idle, then look again at 2000-2500RPM. If it's running not near as lean at higher RPM's, you can rule out a vacuum leak as the cause.
If you can look at PID's with your scan tool, look at the fuel trims at idle, then look again at 2000-2500RPM. If it's running not near as lean at higher RPM's, you can rule out a vacuum leak as the cause.
The thing you are concerned with is a vacuum leak. Looking at the picture, I cannot see a problem, but that doesn't mean one isn't present.
The easiest way to find a vacuum leak is to spray carburetor cleaner on and around any area you suspect might be leaking, or could possibly leak and watch the oxygen sensor output. The oxygen sensor output will drop to around zero volts and the short fuel trim will also reduce or even go negative if a leak is present while you spray carb cleaner on it. Listening for a change in engine RPM can also be done if you don't have a capable scan tool, but this is not a very reliable method to find smaller leaks.
The easiest way to find a vacuum leak is to spray carburetor cleaner on and around any area you suspect might be leaking, or could possibly leak and watch the oxygen sensor output. The oxygen sensor output will drop to around zero volts and the short fuel trim will also reduce or even go negative if a leak is present while you spray carb cleaner on it. Listening for a change in engine RPM can also be done if you don't have a capable scan tool, but this is not a very reliable method to find smaller leaks.
1 of the lines from the catch can that runs to the valve cover does not have a pcv valve on it that line has alot of oil in it do u think that could be it? do u think i need to get a pcv valve
