hesitation under load.

monaco75

monaco75

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The 400 in the cordoba has me stumped. The engine will idle/rev fine in park. Usually runs fine in gear when cold. Lately shes been hesitating under a load while in drive. Ill take off from a stop, and it doesn't want to go, but won't stall. Once up to speed, its not as noticible. It normally does it when the A/C is on. It would stop doing it once I turned the a/c off, but now its doing it no matter what.

I did a tune up (plugs, cap, and rotor), and she ran great for 3 days afterwards, with no problems. Today coming home from work with the a/c on it started acting up again.

I don't see any vacuum leaks, or what not.. I've got a new fuel filter to go on, but havn't done it yet. Theres a clear filter on it now, but doesnt look plugged.

Any suggestions?
 
I had the same symptoms on my 440, I did the same song and dance as you and it turned out to be the power valve.
 
Running A/C in November? Geez... Coil, pick up ? While I'm not sure who I'm dealing with, so I do not intend to insult, but I know of some guys who say "oh I don't have a brass feeler gauge so I'll just use a steel one". Great! you just bollocks it up!
 
If the secondary tune up made any difference and then went back, my first instinct would be to check the coil. Spray it with a little water and see if there are any arcs and then check it for resistance values at room temperature. There should be factory service specs for its ohms values. If its an accelerator pump, you usually can "feather" the throttle to compensate for a week one. Not knowing your skill level, these are easy checks you could do in just a few minutes. BTW a vacuum leak will usually either cause idle problems or higher than normal idle so I wouldn't dwell on that too long. I usually do a "brake stand" without getting to the point that the tires spin to duplicate heavy loads, just don't do it for more than a few seconds or too many times too close together because it heats the trans fluid very quickly.
 
for the editors out there... misspelled "weak"
 
3C's & a D? said:
Running A/C in November? Geez... Coil, pick up ? While I'm not sure who I'm dealing with, so I do not intend to insult, but I know of some guys who say "oh I don't have a brass feeler gauge so I'll just use a steel one". Great! you just bollocks it up!
Click to expand...

Sears or any hardware should have brass feeler gauges in stock if your ever in that situation, but lets look at the secondary coil first. No oil leaking, no voltage leaking and resistance values in spec at proper temperature...
 
3C's & a D? said:
Running A/C in November? Geez... Coil, pick up ? While I'm not sure who I'm dealing with, so I do not intend to insult, but I know of some guys who say "oh I don't have a brass feeler gauge so I'll just use a steel one". Great! you just bollocks it up!
Click to expand...

75 degrees here today. LOL!
 
Thanks guys! Idk why, but i never saw these post all day till just now.

Alright, today i sprayed some brake cleaner around the intake/carb, have no leaks there. I then took the carb off, dissasembled, and cleaned it out. All looks good there.. I swapped out the orange boxes with the one from the bluesmobile. None of this did a thing. Tomorrow I'll swap the coils between the cars. I ran out of time tonight.

This is starting to piss me off! The symptoms lessen when i stand on th throttle, or down shift, and get the rpms up.
 
The carb is an eddy 4106. It really feels like a fuel problem, but the engine is missing too. idk..
 
Wollfen said:
I'm sticking with Accelerator pump.
Click to expand...

he could be on to something, try the "feather the throttle" method of taking off from a stop... that accelerator pump is very much the same as a cheap squirt gun pump... when it wears you need more pumps to get a squirt. coil swap couldn't hurt, but if they are different part numbers it may still not run right.
 
Now I'm not getting any spark out of either coil... Pretty sure the car won't be making it to the show saturday. Ugh
 
monaco75 said:
Now I'm not getting any spark out of either coil... Pretty sure the car won't be making it to the show saturday. Ugh
Click to expand...

I sent you a pm with my # in the wee hours this morning when I first woke up. I'm home with the flu so I check the phone every few hours between naps. Text me and maybe we can get you there... cause I would hate both of us to miss it.
 
commando1 said:
Park down by the A-bodies then.... :D
Click to expand...

I wont be there... not out to spread the disease... besides I still work off of mom's rule "If you're too sick for school, you're too sick to go out and play."
 
Thanks cantflip! Ill get with you here in a few.

I finally got the car to come back to life. I switched the ECU's back out. I don't think the one from the bluesmobile was grounding correctly. Also went and picked up a new coil.

Its gotta be the accelerator pump. She still running crappy. A little better with all the new ignition parts, bit still boggin.

Heres a crappy phone vid. Can kinda tell when shes bogging down. Cant really see the car vibrating and what not...
https://youtu.be/IQ2G61FZWyM

Anywhase I don't care damn't. Shes going to the show tomorrow whether she likes it or not. Luckily its mostly open road/highway. I think she'll make the 2 hour journey. Ill order an accelerator pump monday.

Thanks guys!
 
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