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I think it might be the fuel pressure regulator, since pump is new. Check your pcv. I've read that a bad pcv valve can cause similar issues to show up on cylinder #3. Good luck! I've probably got 100 hrs into trying to diagnose this problem.
I wish replaced that as well ...I am coming to the conclusion it is probably the icu (ignition control unit) which would explain the random misses...Very expensive part that no one wants to buy unless they are for sure that is what it is. Next door neighbor works at a high end shop with all the gadgets is taking it in on Monday. This is frustrating him as well
Could be. Fortunately I have a fsm which has been very helpful with showing how to test things, but the igniter is one thing I haven't found how to test. It shows how to test the coil, but not the igniter. You check fuel pressure and compression yet? Have you scoped your injectors to make sure they're firing?
new motor as of two months ago new injectors replaced the regulator today...From what I gather the random miss happens mostly on #3 which would point to icu versus low pressure(which is not the case). As I have pulled wires I noticed a lot less spark on #3 then any of the others...Could be a coil I guess but why such good spark except #3...I have noticed this is a common problem with these pickups with 20 + years on them even with new motor blah blah blah...What I did notice is no one on their threads have replaced the icu part.
My celica would run until the motor warmed up then would die until it cooled down, over and over. Fortunately, I had another pickup with a spare I threw in and it worked.
Mine does it cold or warm, worst at idle. Another thing you can check is your vf signal. There's a port in your diagnostic box labeled vf and you are checking voltage, depending on voltage will tell you if you're running rich or lean. http://www.well.com/user/mosk/Vfsignal.htm, good write up on vf signal, running some different test, and what they mean.
Wow that sound like that valve on th underneath of your throttle body....Cant remember the correct name for it off the top of my head but it is a air valve that goes out because it has wax in it ..Has two water lines that go to it. It closes the valve/extra air down when it heats up
Wow that sound like that valve on th underneath of your throttle body....Cant remember the correct name for it off the top of my head but it is a air valve that goes out because it has wax in it ..Has two water lines that go to it. It closes the valve/extra air down when it heats up
You're talking about the iacv. I thought that was my issue, but after swapping to a 92 upper intake and throttle body it still misses.
I am having serious issues getting all the air out of the cooling system.
Check for leaks.
Are you using Toyota Red antifreeze? I've found the red color helps locate the smallest of leaks.
Once I got rid of two small leaks I thought I was good. Wrong
Check the radiator cap.
If it doesn't hold pressure and open at the correct point the system will never function correctly.
I had purchased a new radiator cap shortly after I purchased the truck so I assumed it was good.
Once the small leaks were fixed and the system was building good pressure the NEW cap started leaking because one of the rubber gaskets was faulty from the start.
Check the hose that connects the radiator to the recovery tank. Think of it as a vacuum hose!
If that hose doesn't hold vacuum the radiator will be drawing in air through the leak instead of coolant from the recovery tank when it cools down.
Remove the hose and see if it holds vacuum. Make sure it seals at both connection points and doesn't have any leaks.
Check the heater control valve position. #3 in the picture below
If it's only partially open it will trap air in the heater core.
Like mine, a few people have reported their's wasn't adjusted to allow it to fully open.
I just disconnect the cable from underneath the valve and push the valve fully open/hot position when I'm bleeding the system.
I like to leave the cable disconnected and the valve wide open for a few days until the system remains at the same level all the time.
Some people disconnect the heater hose and fill the heater core from there.
I haven't done it but I've read about a couple of people who have removed the thermostat and filled the block with coolant to avoid air pockets in the block.
Because air travels upward you want the fill point to be the highest point in the system
Two other things I do to drive air up and out is;
1. Jack the front end up as high as I can get it when filling and purging air from the system.
2. I use the Lisle no spill funnel that places the fill point higher than the heater hoses. I also use the 4-5 inch extension tube that comes with the 24680 kit to get it WAY higher than it needs to be.
The next morning before I start the engine I place some masking tape on the tank and mark the level.
I always look at the level first thing in the morning before I start the engine. The height may lower a little the first day or two but if after a few days the level hasn't stabilized I know there's a leak somewhere.
If you do all that and have no leaks you should be good to go.
Thank you! I will try that. I started checking more wiring because I'm trying to figure out why my brand new denso fuel pump is only putting out 30 psi. So, I started checking power to the pump. My battery has 12.2 volts with engine off, but my circuit opening relay is only getting 11.3 volts coming in and 10.8 volts out. I have 12.02 volts coming into and out of my efi fuse. I jumpered b+ and fp, which should send direct power to my fuel pump and with the ignition on at the fuel pump connector I'm getting less than 1 volt. My theory is that my fuel pump isn't getting enough power to give me adequate fuel pressure. Anybody know if that is correct to assume? My guess is my circuit opening relay is not working correctly, shouldn't be dropping .5 volts going out, and also that the fuel pump power wire between said relay and fuel pump plug has an issue.
Thank you! I will try that. I started checking more wiring because I'm trying to figure out why my brand new denso fuel pump is only putting out 30 psi. So, I started checking power to the pump. My battery has 12.2 volts with engine off, but my circuit opening relay is only getting 11.3 volts coming in and 10.8 volts out. I have 12.02 volts coming into and out of my efi fuse. I jumpered b+ and fp, which should send direct power to my fuel pump and with the ignition on at the fuel pump connector I'm getting less than 1 volt. My theory is that my fuel pump isn't getting enough power to give me adequate fuel pressure. Anybody know if that is correct to assume? My guess is my circuit opening relay is not working correctly, shouldn't be dropping .5 volts going out, and also that the fuel pump power wire between said relay and fuel pump plug has an issue.
For testing only, run a wire from the battery to the pump and see if you fuel pressure hits the number. If it does, I think you are on the right track.
02-21-2015, 08:04 PM
e igniter. You check fuel pressure and compression yet? Have you scoped your injectors to make sure they're firing?
