1990 7.5 Code 41 (lean) High Timing
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Joined: Jun 2015
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65 Traction control system no change
I’ll probably replace the throttle position sensor since it seems to be giving some intermittent issues. Sometimes, randomly, I will have a hard shift so that could be the problem. Wiring all looks good.
As for the code 33, I’ll have to do more research on. I still have my EGR valve and pipe but the special fitting at the manifold was broken, it’s about $120. So I’d like to keep the EGR valve off if possible.
I’ll probably replace the throttle position sensor since it seems to be giving some intermittent issues. Sometimes, randomly, I will have a hard shift so that could be the problem. Wiring all looks good.
As for the code 33, I’ll have to do more research on. I still have my EGR valve and pipe but the special fitting at the manifold was broken, it’s about $120. So I’d like to keep the EGR valve off if possible.
I fought an E4OD shift and false neutral problem for a couple years. I replaced the MLPS bit that didn’t help. Eventually I got a TPS code so I replaced the sensor. I sold the Bronco a few months later but it ran better the few months I had it.
So is the pipe open to to air?
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Fleet Mechanic
Joined: Jun 2011
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From: Conway, South Carolina
No such thing as traction control on these trucks
I fought an E4OD shift and false neutral problem for a couple years. I replaced the MLPS bit that didn’t help. Eventually I got a TPS code so I replaced the sensor. I sold the Bronco a few months later but it ran better the few months I had it.
So is the pipe open to to air?
I fought an E4OD shift and false neutral problem for a couple years. I replaced the MLPS bit that didn’t help. Eventually I got a TPS code so I replaced the sensor. I sold the Bronco a few months later but it ran better the few months I had it.
So is the pipe open to to air?
Currently the EGR valve and pipe are off the truck. I installed an EGR Simulator into the EGR plug, EGR block off plate on the intake, and a brass pipe plug into the exhaust manifold.
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Another example of the simulator plug not working as advertised. There is only one resistance so the computer does not see a voltage change when the EGR is commanded open.
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Fleet Mechanic
Joined: Jun 2011
Posts: 1,324
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From: Conway, South Carolina
Thanks. that I what I was reading elsewhere. This in my first truck with an E4OD. Previous models had the AOD or C6. So I didn’t need to switch the OD switch and the KOER test never prompted me to.
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Fleet Mechanic
Joined: Jun 2011
Posts: 1,324
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From: Conway, South Carolina
I’ll probably end up putting the EGR back on later once I can stomach the price for the manifold adaptor.
Besides that it seems there are conflicting opinions about the code. Some say code 33 won’t set a check engine light. Others say it will. In my case. Looks like a code 33 sets a check engine light.
Hotshot
Joined: Jun 2015
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or you could have the valve (with block off plate/gasket) and sensor on the plenum with the vacuum lines and solenoid.
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Fleet Mechanic
Joined: Jun 2011
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From: Conway, South Carolina
that might be worth a shot. Good to test a theory anyway.
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Fleet Mechanic
Joined: Jun 2011
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From: Conway, South Carolina
You need to get what is called a piston stop tool. You thread it into #1 spark plug hole, and rotate the engine BY HAND SLOWLY. You then mark the balancer where the timing pointet is showing. Then rotate the engine in the opposite direction. Again mark the balancer where the pointer shows. Then measure the distance between the two, half way is your REAL zero degrees. There is a possibility that over the years the balancer has slipped on the rubber ring. And 10 degrees is really 14 or 15 causing your spark knock. My 5.0 used to be off by 4 degrees. I haven't checked it in a few years, but ill bet it has moved again.
Start there. Because if you have a mechanical problem, it will make it harder to chase a computer issue.
Start there. Because if you have a mechanical problem, it will make it harder to chase a computer issue.
I also noticed a mark placed at the 0 degree mark on the balancer, My guess is the balancer has slipped at some point with a previous owner, and now slipped again. (Timing before I made adjustments was at 0 degrees, now with timing at 0 degrees I get light spark knock) Then when I adjusted the base timing to 10 degrees BTDC my timing was so high it was causing the spark knock, and then the lean issue was due to the injection timing being so early since injection timing is also based on the PIP readout from the distributor.
Untimely I will replace the balancer in the near future.
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From: Ottawa, Ontario
Is the idle speed high? It should be 650-700rpm but if it is higher the computer will throw more advance at it which then makes the idle speed even higher.
A slipped balancer is a good possibility here, you don't need any special tools to find TDC on cyl 1 a piece of rigid coat hanger wire will do, you just remove the spark plug and while slowly rotating the crank with a breaker bar insert the wire to feel for the piston as it comes up to TDC, it will be real obvious when it does. That should correspond with the timing mark on the balancer indicating 0, if it doesn't you found your problem.
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Fleet Mechanic
Joined: Jun 2011
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From: Conway, South Carolina
Well removing the Spout plug disables computer advance which is 20deg in this case, so it shouldn't be a surprise.
Is the idle speed high? It should be 650-700rpm but if it is higher the computer will throw more advance at it which then makes the idle speed even higher.
A slipped balancer is a good possibility here, you don't need any special tools to find TDC on cyl 1 a piece of rigid coat hanger wire will do, you just remove the spark plug and while slowly rotating the crank with a breaker bar insert the wire to feel for the piston as it comes up to TDC, it will be real obvious when it does. That should correspond with the timing mark on the balancer indicating 0, if it doesn't you found your problem.
Is the idle speed high? It should be 650-700rpm but if it is higher the computer will throw more advance at it which then makes the idle speed even higher.
A slipped balancer is a good possibility here, you don't need any special tools to find TDC on cyl 1 a piece of rigid coat hanger wire will do, you just remove the spark plug and while slowly rotating the crank with a breaker bar insert the wire to feel for the piston as it comes up to TDC, it will be real obvious when it does. That should correspond with the timing mark on the balancer indicating 0, if it doesn't you found your problem.
The engine sounds a lot better now and has that low down grunt like it used to.
5th Wheeling
Joined: Jun 2025
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sorry I guess I thought you asked why. O2 sensor is in its stock location. It’s down stream about halfway of the transmission (roughly under the passengers seat). And by smog I mean the smog pump and cat plumbing. Simply unbolt it from the bracket and remove the pump and air plumbing that originally went in the cat. On my 460 the factory cat was located further down the exhaust system, under the extended cab portion flooring.
EGR simply runs out of the driver’s manifold and into the intake behind the throttle assembly. I installed a pipe plug into the manifold and a block off plate onto the intake.
EGR simply runs out of the driver’s manifold and into the intake behind the throttle assembly. I installed a pipe plug into the manifold and a block off plate onto the intake.
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Fleet Mechanic
Joined: Jun 2011
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From: Conway, South Carolina
My plan is when I get all the bugs worked out to take the restrictors out of the intake, let the engine breathe with the F3TE heads and if the lean issue arises get an adjustable fuel pressure regulator.
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