Something weird with the idle/throttle

[DesertSprite]

Hello once again,

Okay, here's this weeks problem:

Driving around town for a while, I slow to a stop and the car begins to sputter and lose it's idle, then it just stops completely. The car was warmed up, driving fine beforehand. When it died, it seemed to trying to maintain the idle as it sputtered.

Weird thing is...I pushed a couple of feet just to get it out of the way of parking lot traffic, then tried to start it up...boom, fired right up. ??

Drive it maybe a mile down the road towards home and it does it again. This time in between shifts (1st to 2nd). As the RPM's were coming down it just lost it's ability to stay going.

Being that my Wife was with me and we were headed out for the day, I got it home and put the cover on it and took out the 4Runner. So, needless to say I haven't had anytime to check it out yet.

I'm thinking it might be some kind of vaccum leak or something. The thing has been idling quite high lately. I'd say approximately 1200-1300rpm's at idle.

Any ideas?

Mahalos,
Joel

/ubbthreads/images/graemlins/thirsty.gif

 

[tony barnhill]

What type distributor you running?

 

[DesertSprite]

Lucas 25D.

 

[tony barnhill]

Check your condensor

 

[DesertSprite]

Got it. What should I be looking for?

 

[lesingepsycho]

ballast resistor?

JACK

 

[DesertSprite]

Don't have a ballast resistor. When I replaced the coil I used the Lucas Sports one.

Joel

 

[DrEntropy]

Runs fine then konks out... does it again after another spurt... Sounds fuel-ish to me. 25D, points 'n condenser I'd expect to just ~quit~ and not start again. Condenser is cheap at NAPA, A/Z, etc. tho. Swap it out and see.

Fuel pump demonstrably good? I'm just stabbin' here, so pardon if that seems silly.

 

[jcatnite]

I was thinking fuel too doc. I was wondering if the fuel tank vent wasn't possibly stopped up some how. Could be a lot of things, as usual, I would rule out ignition problems before doing much else. A clogged fuel filter did to me, exactly what Joel described. When I bought my car, it had a rusty tank and the PO "fixed" it by installing a small filter between the tank and the fuel pump. Took me a bit to find that one...lol
JC

 

[DrEntropy]

I know this is a segue, but: has anyone ever put a pressure gauge in-line to SEE what it is 'normally' while running? I may do that just fer S&G's. That "curiosity" thing again.

 

[jcatnite]

I did but, I've got an aftermarket electric fuel pump on mine. Seems the rust in the tank kept trashing those "expensive" mechanical pumps(PO's exact words). I kept about 3psi through the entire range of engine rpm. The car ran extremely rich when I bought it and I was wondering if the pump was overdriving the needle in the carb. Not the case for me though, the over rich was caused by an eroded needle coupled with pitted points and spark plugs that looked like they were installed by Fred Flintstone.
JC

 

[DrEntropy]

Neat. Good "telltale".

 

[DesertSprite]

I have a new condenser right here and I have a new fuel pump as well, so I guess I'll swap those out and give it a try.

Fuel pump seems to be working fine to me. But then again, I'm no expert here. When I turn the ignition to "on" I can hear the fuel pump doing its thing, but it doesn't sound like anything is wrong with it.

Unfortunately, this might have to wait until next weekend as I'm going out of town this weekend. Don't you hate that? You want to drive your Spridget on Friday to work because its supposed to be nice, but then it craps out on you. /ubbthreads/images/graemlins/frown.gif

mahalos,
Joel

 

[DrEntropy]

A good reason to have more'n ONE! /ubbthreads/images/graemlins/devilgrin.gif

 

[drooartz]

I've started to think that having 2 LBCs might be a good thing. Of course, not sure my wife would appreciate it, and I'm too big to sleep in the Tunebug!

 

[lesingepsycho]

I don't know anything about the Lucas Sports coil but if it isn't internally resisted, it will still scorch the points and cook the coil. After a bit of driving, (it was about 20-30 minutes with my car) the coil heats up from getting too much voltage, that extra heat is then passed on to the condensor which can no longer keep the points from arcing and you start losing you ignition little by little. After 5 minutes or so of sitting, things will cool down and then you'll be able to drive for awhile again. It took me YEARS to diagnose this problem and I replaced EVERYTHING in the fuel and ignition systems at least TWICE and all along it was a $10.00 ballast resistor. It's certainly worth checking out is all I'm saying! My car has never broken down since I installed a ballast resistor whereas it used to break down everytime I drove it.

JACK

 

[DesertSprite]

Jack - I'll certainly look into it, but I was told not to install a ballast resistor in the ignition system if the car was never originally equipped with one. ??? I don't know. It seems like this ignition nightmare won't go away.

DrEntropy - if you can convince my Wife to let me buy a nice E-type here in a few years, I got no problem with owning 2 LBCs!

Joel

 

[Matthew E. Herd]

Joel, if your original coil had a ballast resistor internally, then you wouldn't have had one that you knew about. However, if the sports coil which replaced it doesn't have one, then you'll need to add it. One good way is to measure the resistance of the coil. However, I don't remember what the numbers are.

 

[DesertSprite]

I don't think the original coils had them. Did they? This is for a 1275cc motor. I know the sports coil does not have one.

Joel

 

[Bugeye58]

The sports coil is an internally ballasted coil. Typical resistance readings are in the 3.0 Ohm range. An externally ballasted coil will Ohm out about 1.5-1.6 ohms. DO NOT install an external ballast resistor on an internally ballasted coil.
Jeff