Motor help

Hey guys and gals! I need some help with my mustang's motor. It not running to smoothly. It's a 289 with an AOD transmission. Holley 4-barrel carb. and chevy style HEI(don't give me crap over running a chevy distributor on a ford). What it's doing is when in overdrive at around 35 mph, the motor seems like it get really out of balance, like a missfire.(it's happens just after it shifts into overdrive or even after it goes into 3rd sometimes, like the motor looses power and has trouble turning the transmission). It shakes the hell out of my car. I have to kinda prime the gas pedal and it clears up. Also when you accelerate it hesitats really bad, bogging down. Once i get it warmed up to temp and get it above 35 mph it runs great. So what do you guys and gals think it could be? I checked all the spark plugs the other day, they all were white/grey, seemed to be running lean a bit. I'm thinking the jetting maybe wrong?? I figure I ask before I go buying a bunch of stuff to change the jets and that not be what it is!

Thanks
Mike

OD at 35MPH may be putting stress on the engine (lugging). OD should be locked out around town (selector lever). How high is the rear gear?

Describing once it warms up may also indicate a mis-adjusted/malfunctioning choke.

All of this is assuming the AOD is in good condition and the cable is adjusted correctly.

(don't give me crap over running a chevy distributor on a ford)

...sigh...

I do lock out the overdrive ing town driving around 35mph, but even with it locked out it will sputter and hesitate even in 3rd gear. I'm pretty sure that its not the choke because when I start it, it will high idle then after I start driving it and the temp gets up it will kick off and regular idle. Even with the choke off it will hesitate and bog. The rear end gear is a 3.00:1. The orginal gearing that i had in it was a 2.89:1 gear ratio. It's a 8 inch rear end. I don't think that would cause it to be a problem. I had a thought that it could be some bad spark plug wires because the wires i got were cut to fit wires. Though that was alittle riged. Maybe the wires weren't getting enough spark to the plugs. The trans is one I got out of the junk yard. I cleaned it out and put a new filter and fluids in it. I adjusted the TV cable to 35 P.S.I. from the tv port on the side of the transmission. I think my next step is to put new wires on it and see it that is the problem.

Sounds like you have multiple issues. I personally prefer cut to fit wires because I can route them the way I like. Measure them with an ohm meter - if they all ohm out the same or nearly so, they are fine. You could have an air leak and or accelerator pump/shooter issues. Lean jetting will show up as a surge that would get worse at higher speeds, not better. The plugs would also be bone white, usually. Also check the basics - make sure the plug wires are set up in the correct firing order and that plugs firing next to each other in the firing order don't have their wires routed togehter. There could also be carbon tracking or some sort of misalignment in the distributor causing crossfire.

Originally Posted by 67mustangcoupe289

What it's doing is when in overdrive at around 35 mph, the motor seems like it get really out of balance, like a missfire (it's happens just after it shifts into overdrive or even after it goes into 3rd sometimes, like the motor looses power and has trouble turning the transmission). It shakes the hell out of my car.

I have to kinda prime the gas pedal and it clears up.

Also when you accelerate it hesitats really bad, bogging down. Once i get it warmed up to temp and get it above 35 mph it runs great.

Let me try again. With an AOD (and pray it isn't the trans and/or torque convertor), the car may hesitate between direct and OD. It depends upon several factors, one smooth engine power and the other rear gearing/changing at correct engine torque point.

If it does run OK after a few miles, again look at the choke for releasing/opening too soon. When you say you feather the fuel, you are enriching the mixture to make up for a lean condition possibly caused by a malfunctiong/misadjusted choke.

Also take an engine vacuum reading at that point and see if the power valve may be fluttering. I am assuming with the BOWTIE IGNITION that it is electronic advance and not engine vacuum?

I will now leave you alone...

I think I found my problem... The little bow tie distributor is giving me a problem... I think the coil is bad.... correct me if im wrong.... I did a ohm test on the C- and B+ post and got a reading of about .75k ohms. Then I did a reading from the High tension coil output to the C- and got infiniaty... should read 9.2k ohms.... Am I right?? Quick answer would be nice!!!

Thanks,
Mike

Curiosity is getting the better of me, why a bow tie ignition?

Originally Posted by Gydyup

Curiosity is getting the better of me, why a bow tie ignition?

You broke the code...

Originally Posted by 67mustangcoupe289

I need some help with my mustang's motor. It not running to smoothly. It's a 289 with an AOD transmission. Holley 4-barrel carb. and chevy style HEI(don't give me crap over running a chevy distributor on a ford).

How to test an ignition coil

should have put msd on it other than a chevy ignition... jokin... but i found all my problems doing some dia. today. Found the #2 and #3 wires were crossed for some reason.... dont know how that got that way.... probably me not paying any attention.... i believe the coil was bad.....bought a new one fixed that.... but got another question you guys and gals might know.... the vacumm advance and the mechnical advance(weights inside the cap) of the hei distributor.... i keep getting a back fire every once in a while.... and the vacumm advance doesn't seem to be working when i hook up the vaccum line.... you can stick an allen wrench in there and turn a screw.... is the to adjust it??? and if so how much should i adjust it with running off a port for vacumm advance off my holley carb??? when you have the line off and give the engine gas it doesn't seem like much vacumm off that line than having it hooked up to full manifold vacumm....