My understanding is that those are the only 4 areas of vacuum, 2 EGR, 2 manifold off the black fitting. I could be wrong though.
1991 3F-E De-Smog Performed
- Thread starter spdwaver
- Start date
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maybe that black thimble filter is clogged? and not opening the fuel pressure VSV? or bad fuel pressure VSV? or both?
I have no idea what could have it clogged, but it's easy to look. No experience with testing fuel pressure but you can always put a gauge on it and see if it jives with the FSM.
I just remembered that I had washed out the intake plenum with oven cleaner 3X and rinsed it repeatedly. It had black crud built up. so maybe that black filter got clogged up worse in the cleaning process. oven cleaner works great BTW
checked that black filter and not blocked
today I swapped out the ICV and the fuel pressure regulator. now it is just vapor exhaust. sounds good and does OK on the flat, but climbing a hill was 10 MPH less than when I got it. this is after a total de-smog and the 4 port injectors. I will swap out the MAF mañana. Any ideas of what to do next? and the idle when hot fluctuates. This is what it did before the head blew.
the stall out at idle when stopped after some higher RPM driving is a killer. then it is tough to start up again.
RE: "code 71 can be defeated by shorting out the EGR temp sensor wires" where are these wires? I am not seeing a loose connector floating around.
There is a temperature sensor on the EGR valve, in cali smog trucks. If you removed that there should have been a plug in the area where the EGR was. Short those wires.
this was an AZ FJ80 and there is a grey plug on both the 91 & 92 but nothing ever connected
Open connector or does it have a jumper in it?
hey, what about the Power Brake Booster needing vacuum? my brakes are not functioning at 100% especially when the RPMs drop coming up to a stop. I need to keep the RPMs up to 2000 to keep any brake pressure
Sounds like you got yourself a bad vacuum leak guy. Have you got a vacuum gauge on it? After you fix you vacuum leak adjust your timing.
I have a 94 and keep popping code 71. Cleared it three times so far. I do not see a smog pump. I will loop the primary vacuum ports, and loop the other side with a coupler. I will short the temp sensor.
I've yet to pull my EGR valve for inspection, but I'm certain it's clogged closed, or seized open, or just anything wrong.
Should I fill the valve with metallic JB Weld to ensure it passes no exhaust vapor?
10mpg right now.
No emissions testing here in TN.
I've yet to pull my EGR valve for inspection, but I'm certain it's clogged closed, or seized open, or just anything wrong.
Should I fill the valve with metallic JB Weld to ensure it passes no exhaust vapor?
10mpg right now.
No emissions testing here in TN.
Yank the EGR and short the sensor wires. Unless you just enjoy playing with emissions equipment.
Shorted the sensor and looped the vacuum ports to each other.
No more crazy rattling on cold start now. Idles smoothly. Code 71 has yet to return. The truck does seem to run better. Now I need to verify the EGR valve is actually closed.
Sure wish I had that problem haha
What issues do you have?
