And I still get 9.97 MPG

I rebuilt the head, and that was a feat I've never attempted.

Now, I've read and read and changed just about everything, and still get lousy gas milage and a hesitation during driving.

I also get a sputter once in a while at idle.

Also seems feels like it slows on it's own without me lifting the gas pedal. Then smooths out and runs good.

Uh....1990 MM, 2.4 FI, auto, doesn't seem to have the OD working either.

There is one thread I was reading that seemed to be helping me, but I don't remember which one it was, and can't find it.

I'm so freaking frustrated and the wifey is getting on me to trade it in.

NOT gonna happen till I figure this thing out.

Biketober fest has come and gone, so getting it to run good enough for Daytona bike week in Mar is the goal.

Thanks for any and all help given. All suggestion will be greatly accepted.

Are you setting the Timing correctly? you have to ground a pin to put the ECU in "Timing mode" to set the base timing correctly. Pop Off the cap and ground the pin inside.

Attachment 17830

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Originally Posted by LSR Mike

Are you setting the Timing correctly? you have to ground a pin to put the ECU in "Timing mode" to set the base timing correctly. Pop Off the cap and ground the pin inside.

Attachment 17830

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Ground to the engine or is anywhere good enough?

Any where metal will work, I like to usually use a ground point though.

I'm just posting to be subscribed so I can follow this. My mileage isn't much better (85 4g6b weber conversion) and I'd like to see what happens. I'm getting about 200-230 miles on 15 gallons. I'm pretty sure I need to rebuild it it runs anyway like they do which is why we like em.

Well, grounded the wire, hooked up the timing light, marked the slot on the harmonic balancer, loosened the distributor, started it up.

No mark to be seen, moved the distributor, shuts off. Will only run with the dist. pushed to the max. Still no mark.

Pointed the light on the other side by the alternator, there it is. So, I'm guessing something is not lined up.

I did move the distributor a tooth, just to see what happens, same thing.

But, does run a little better. A little smoother, still has a skp at higher speeds, but smooth in the 35 to 40 mph area.

Over drive still not operating.

Don't know if gas mileage improved any. But, seems a frontal engine tear down is in my future.

Geeesh, I've had this little MM for years, and just can't get anywhere's with the running issues.

I've been holding off on other issues, till I get it running right.Attachment 17855

Once you have determined the distributor is in right and you can confirm the timing belt is installed correctly, I'm gonna ask you to try the dynamic ignition timing technique I've recommended in other posts.

I had an EFI GM family 2 engine that went 'o.k' but was pretty lack lustre to drive. After it blew a timing belt and I reset the ignition timing, I pointed a timing light at it and did an experiment on the ignition. I under gapped the plugs by 0.5 mm and held the engine rpm @ 2,000. Swinging the distributor back and forth gently I found a sweet spot and the engine's rpm would peak. Then I dialled it back just a touch to allow for the engine being under load. Took it for a drive and it was the best it had ever run the entire time I had owned the car... Pulled like a train and was nice and responsive.

If it helps on the OD issue. I heard of one of the guys here that couldt get his overdrive to work. He found later that the transmission had a separate ecu and that was burnt. He got one from a junk yard and the OD started working..

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Originally Posted by Jonleo

If it helps on the OD issue. I heard of one of the guys here that couldt get his overdrive to work. He found later that the transmission had a separate ecu and that was burnt. He got one from a junk yard and the OD started working..

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Would you happen to know where this separate ecu might be located?

the auto ecm is on the newer trucks 93 and newer - not sure if yours is that new.

nope.....mine is a 1990, so looks like I'm screwed on the OD.

Wish now, this thing was 5 speed. This automatic is getting expensive.

there is a black wire that plugs into a sensor right next to the carb. Ground that to the intake - it is the O/D sensor wire. The sensor is just a temperature switch that closes when the motor reaches operating temperature. The O/D will work at all times when selected with the button on the shifter.

And the hits just keep on coming............................

Finally got the check engine light to go out, doesn't throw code for TPS anymore, just the bottom code which says it's normal.

Ran better for a moment, but still hesitates on take-off, and jumps up and down on accelerator when trying to cruise at normal speed.

Seems to be getting a little better gas mileage, I think, haven't filled with gas to calculate.

Just noticed the gas needle doesn't move quite as quick as it did prior.

Checked the idle control valve with the meter and it checked out with a ohm reading of 11.5, well in between 5 to 35 ohm.

I guess I checked it right.....................I just don't know.

This truck has been throwing me for loops for quite some time......my wife wants me to trade it in this weekend.

Oh yeah, forgot to mention, it does seem, it has a little more power........for as much as a 4 cylinder can have.

well, sad as it may be.........gonna have to trade it in, if the stealership will take it.

After all the work I've done to this little MM, she still won't do right.......now it's back to overheating, and running rough.......wouldn't start over the weekend, pulled the plugs and they were gunked up like crazy.......cleaned them runs, but is starting to spit and sputter again.

So looking to get either a nissan frontier, toyota tacoma...or canyon.

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Originally Posted by mitchi

well, sad as it may be.........gonna have to trade it in, if the stealership will take it.

After all the work I've done to this little MM, she still won't do right.......now it's back to overheating, and running rough.......wouldn't start over the weekend, pulled the plugs and they were gunked up like crazy.......cleaned them runs, but is starting to spit and sputter again.

So looking to get either a nissan frontier, toyota tacoma...or canyon.

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Go with the Tacoma and get the BFG all terrain tires. The stock tires are just waaay too fluffy. I was hating it until I put those tires on it. SUddenly it was like a new truck.

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Originally Posted by 85Ram50

Go with the Tacoma and get the BFG all terrain tires. The stock tires are just waaay too fluffy. I was hating it until I put those tires on it. SUddenly it was like a new truck.

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Did get the Tacoma, and they would not except the MM as trade..........so, guess I'll continue to play with it, but just won't have to chew my finger nails to the nub wondering if I'll make it to work or back again at night.

No mo 15 minute fiasco's with trying to get it started in the mornings, too.

But now, I have the MM, D50 and this Tacoma..................wifey kinda wants me to pick and chose.

Also all these bikes I have strung out thru the garage, storage shed, back yard, bathroom, kitchen is also wearing on her nerves.

So, spring cleaning is around the corner.

When the mileage on my '91 dropped all of a sudden, my check engine light did not stay on but I was able to pull a code for my temperature sensor. It started fine when cold, ran okay but rougher than normal with less power and plugs were fouled. Replaced temp sensor for about $20. and all is good. Bad sensor made the computer think engine was still cold and kept choke on, resulting in all the negative results. Just an idea.

If the OD still doesn`t work. You get hook both the black wires out of the transmission to a toggle switch that runs to ground. When the switch is flicked.. it grounds the wires and you have OD. Once will have 12 volts and 2 are for ground.

My OD didn`t work because the speedo didn`t work. The speed sensor is in the speedo. Once I fixed the speedo, the OD worked.

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Originally Posted by Can1991Ram

If the OD still doesn`t work. You get hook both the black wires out of the transmission to a toggle switch that runs to ground. When the switch is flicked.. it grounds the wires and you have OD. Once will have 12 volts and 2 are for ground.

My OD didn`t work because the speedo didn`t work. The speed sensor is in the speedo. Once I fixed the speedo, the OD worked.

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Ok, thanks bro.......I will look into that.

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Originally Posted by 85Ram50

Go with the Tacoma and get the BFG all terrain tires. The stock tires are just waaay too fluffy. I was hating it until I put those tires on it. SUddenly it was like a new truck.

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Well, I got the Taco, and it had good tires (tread I mean) from Dunlop on there.

Heading to Florida, just entering I-16, and heard a noise, pulled over and this happened.

So daughter bought all new BFG. She's such a great daughter...................:-)