Hesitating issues on the old EB CFI - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

carazy · 01-29-2003, 04:06

Hey peeps got a question for you.
my car is hesitating when under load.
It starts perfectly and idles fine and even drives perfectly with no problems till it reaches running temp.
Once it reaches temp it misses when under even the slightest load. It's not horrible and it's still drivable but I feel that if I keep driving it whatever is on the way out will die. I don't like that idea.
I checked the dizzy cap and that was dirty as hell and the rotor button had crap all over it. I pulled out the dizzy and checked it all out and replaced the cap and rotor button with known good ones I had laying around.
The dizzy looked fine but it's still doing it.
I noticed today that with the air con on as the car got to about 1/2way on the temp guage (the highest it goes) It gets considerably worse and looses all power.
As soon as it cools down it drives fine again.
My theory is this.
It's either the TFI (electrics on the dizzy I think its a TFI unit)
or the Coil.
It doesn't feel like leads as it's to violent a miss to be a lead (unless there all stuffed!)
Tommorrow I'm going to change the dizzy with TFI unit over with a known good one and change the leads (have a spare set of new ones at home to)
if that fails I'm changing the coil.
Is there anything else I'm missing that it could be?
The only other thing I could think of is the ignition module relay over near the fuel relay. (Got a spare one of those to)
Any ideas people? If I fix it I'll report back.

Clutterz · 01-29-2003, 15:04

Welcome to my world. I've been having this problem (or similar) for quite a while now and haven't been able to get it sorted.
Does yours do it all the time when its hot or only off and on? It happens to my car occasionally but mainly when i'm cruising on the freeway or accelerating hard out of corners.

I have changed my coil with no luck, dizzy cap, leads, fuel filter and a whole bunch of other stuff to no avail. I am of the opinion that it can now be only 1 of 2 things. either the ignition module or the fuel pump.

I replaced my fuel pump with one I picked up from the wreckers and the problem got much worse. My mechanic tested it and while the fuel pressure was ok the fuel flow was crap. When he put my original pump back in the problem went away completely for a few days and then started happening again as soon as I started giving the car a bit more stick. As soon as I have the cash I'm going to put a brand new pump in and see how it goes.
I'll let you know.
Please post up here if replacing your TFI works as I'll be interested to see.

SiX_iN_a_RoW · 01-29-2003, 17:13

carazy, have you checked base timing? Whens the last time you cleaned,checked or replaced the spark plugs?
whenever mine gets a slight miss underload its due to the timing ( seems to wiggle its way to 2 or 3 degrees either way at times ) and it only misses when its at running temp.
it could very well be fuel related but it does sound more electrical....stuffed leads can cause a pretty bad miss trust me!

carazy · 01-29-2003, 21:37

yeah leads fixed it.
it's all good now.
It felt horible and I didn't think it could be the leads but I was wrong.
Works a treat.
Now for the best part.... Small exhaust leak near the manifold. It's either the exhaust manifold or the exhaust to the cat. Either way it's got me permission to get my self a brand new exhaust system (extractors, high flow cat, 2.5" system) from the missus.
Bwahahahahahahaha

carazy · 01-29-2003, 21:41

oh yeah the spark plugs are less than 5000kms old and I checked them out when stuffing with the distributor clean as.
So how do I check this base timing? May be able to get the weak little beasty running even better.

SiX_iN_a_RoW · 01-30-2003, 00:19

hhehehe thats always good, that means I am eligible for a new exhaust too!!!!!
Glad to hear your problem is fixed..and so easily.

go here for the base timing, location of the self test plug may differ from the EA though
http://www.geocities.com/xmfordfalcon/Tech_Page.html