I wanted to check the health of my fuel injection system. I have upgraded my injectors from single pintle to multi pintle rebuilt units. I also upgraded the fuel pressure regulator (FPR) to a higher pressure unit. I got a lot of original info from this thread...
http://www.ausjeepoffroad.com/forum/...ad.php?t=92236
Here is the procedure to check the system pressure while the Jeep is running....
My values will be different, as i have the upgraded system. Mine should look like the update Jeeps. Values should be about 41 PSI at idle with the vac hose on and 49 PSI with the vac hose off. With the vac hose off, its the equivalent of running the car at WOT as at WOT, vacuum is almost zero.
So, i needed a gauge to test my pressures. Ebay has a bunch of them, and i chose one that had a heap of adaptors and only cost $30 delivered.
Very easy to do the test. Locate the fuel rail and there is a valve. Screw in the adaptor, start the Jeep and then read the pressure. First pressure with vac hose on the FPR and second with the hose disconnected to replicate WOT (Wide Open Throttle).
My results came back surprisingly good. Pressure was spot on 41 PSI at idle with vac hose on.
Pressure at idle with vac hose off, to represent WOT was around 49 PSI, which is what the FSM for post 1995 Jeeps recommend.
So far, the Jeep seems to be passing all its checks with flying colours. It just seems that at wide throttle, there is no power, and it is also using a bunch of juice. Besides that, around town, she runs perfectly. Starts, idles, runs great up to about 90 kph. Any faster and she falls flat on her face.
Cheers,