Thanks
waiting for it to cool down a bit then going to do a leak down test, I'm kind of leaning towards fuel pressure regulator, but I need to do the leak down to see that too.
I meant cylinder compression and cylinder leak down test. There is nothing wrong with doing the fuel pressure leak down test but I Don’t think that’s your problem
you can read my fuel trim article found in my signature. Negative isn’t good or bad. Large numbers are bad. Changing numbers under different conditions help us find the problem
Thought I would throw this into the mix.....remove the EGR valve, clean it, and the two small intake holes....look for any small pieces of carbon that could be keeping the EGR valve open.
Also, a question to George...would removing the upstream O2 sensor, then try rev'ing engine, see if it goes past 1400rpm....would this be a valid quick test for a clogged cat? CEL will be set as the O2 sensor reading will be wrong. Can only do this for a few seconds.
Thought I would throw this into the mix.....remove the EGR valve, clean it, and the two small intake holes....look for any small pieces of carbon that could be keeping the EGR valve open.
Also, a question to George...would removing the upstream O2 sensor, then try rev'ing engine, see if it goes past 1400rpm....would this be a valid quick test for a clogged cat? CEL will be set as the O2 sensor reading will be wrong. Can only do this for a few seconds.
There are a number of ways to test for a cat induced exhaust restriction. The most conclusive test is to remove an O2 sensor and measure the back pressure at the O2 port. There is also temp measurements, vacuum measurements, tapping on the cat with a mallet, the O2 sensor readings and yes, temporarily creating an exhaust leak by removing an O2 sensor or loosening an exhaust pipe fitting to see if things improve.
04-12-2021, 01:38 PM
