running on three Cyl when cold

[Polar Bear]

Hi,
lately I've had a new problem with my Terc. Days are getting colder and so on, Don't know if that has anything to do with this.

Anyhow, when I fire the car up when cold, she starts just fine, but clearly fires with three cylinders.Not all the time though, say every 10 seconds or so, I can hear it clearly.
If I try do drive it, there's still power left, but as you can imagine, it's not much fun trying to drive....
But when the engine warms up to the normal running temp, everything is just fine. Any ideas what's wrong... head gasket maybe?

I've changed the plugs, plug wires, adjusted the valves, but haven't touched the carb yet.

[Petros]

head gasket would not likely cause that. perhaps moisture in electrical contacts? with loose or corroded contact moisture prevents reliable signal, but after warm up moisture is driven out and it runs normal.. Try cleaning all electrical contacts in ignition system. Clean distributor and use contact tuner cleaner.

[rer233]

check the aap diaph.

[Ace]

Suggest you double check the plug wires and change the distributor cap and rotor also.

[Polar Bear]

Hi,
sorry for the late reply.. and thanks to all for the tips.
I wiggled and cleaned all the electric contacts, and re-checked the valves etc... and for the final task, I checked the distributor cap. Well guess what; the rotor was shot, it had eaten the distributor cap contact points, or rather made deep groves on them. I have changed the rotor and the cap less than 5000kms ago, but I guess that the rotor shaft is so loose( bearings) that given enough revs to the engine, it just spins little out of balance and does the damage... or maybe aftermarket parts are just c*rap and measures /tolerances are way off to begin with.
Well, the problem is solved for now, and she runs just fine.

[celtglen]

...

[Polar Bear]

Part two...

same trouble still excists, but it's gotten worse. I've checked and doublechecked everything that I can think of. still no solution.

*If I use the engine block heater, the misfire is not so bad, but if I start it up cold, in temps between +5 / -5 C, it's total chaos. really bad misfires and she barely runs.

* when the engine warms up, everything is fine. And also, if the weather is cold, say -10C or colder(dryer weather), again, not so bad misfires.

*But.. when the engine is warm, if I hit a puddle of water, the misfire starts again...

either there's two separate problems, or one and only, moisture. But in where could the puddle of water infect the darn thing? Fuel lines under the car?

[larry mcgrath]

i live in cold country 6000 ft so i have a lot of experence with cold start problems .this sounds like the eiecteic choke may be faulty _- check voltage at housing on carb .,or thutch it and it will be hot ,key on.------next check the usualy gray hose adout 2" diamiter hose that goes from air clener to ex manifold ,connected and no holes (duck tape ),in the FSM there is a check to see if ,,,there is a vecume opperated valve in inlet of air cleaner is working this draws warm air from to atomize fuel better when cold ,is working.how long are you letting this warm up? is this comming up to temp ,do you have good heat from the heater. what is your starting puosideures to start when cold ?? are you setting the choke ? Larry

[TURTCEL]

You said that when you drive through a puddle the misfire gets worse. It sounds to me like moisture is getting in to the distributor cap and causing arching. There is a rubber gasket that goes between the cap and the housing as well as a rubber grommet that the dizzy wires go through on the housing (more like a rubber block that is intergrated to the wiring), if either of these is gone or damaged water can get into the cap.

I believe the gasket can still be ordered.

Peace

[Polar Bear]

Thanks guys.
I've checked the tvsv operation, and the cold/hot intake system works too. Luckily I don't have the emission control cr*p installed at all.. just the basic systems. But all the vacuum lines are okay, and everyting works, including auto chocke. Starting procedure includes pumping the pedal about 5 times to ensure enough fuel into the carb. The carb warm up system, not sure about that. I'll measure that.
When the engine reaches about 8 o'clock on the temp meter, she starts to run fine. I get very good heat in to the cabin when she's warm.

The dizzy cap gasket was missing when I bought her, but I replaced it with a DIY rubber one.thickness should be correct on that. I have the Ignitor system installed, and the rubber blug that the wires comes through is fine. There's a hole on the left side of the dizzy, about 10 o'clock, facing side/downwards. should there be a plug too, or is it for ventilation?

Today the temp was about +3C and damp. I did a test, the car was cold, and I took the dizzy cap off, and used a hot air gun ( my wife didn't let me borrow her hair dryer ) and used the lowest setting and warmed the dizzy inside, about 30sec. Put everyting back together, and turned the key. Viola, she started just fine... I coudn't see any visible dampness inside before I warmed it up with the gun. If the o-ring seal(s?) on the dizzy axle is worn, and leaks oil or lets hot oil vapor to enter the dizzy, could that be it?
And if so, could the puddle spray on starter motor or somewhere lower on the engine to cause same symptoms? I can't see how the water would spray all the way up to the dizzy. So there could be two separate broblems after all? I think I'll clean and check everything around the dizzy, contacts, and the o-ring(s?) and then do a separate test; when the engine is warm and running, I just drive it up a ramp, and go under and start spraying water with a flower water sprayer or similar, working may way from the bottom up.

[TURTCEL]

Also, check to make sure that the wires going to the dizzy are damaged or exposed. There is a green plug that is for the dizzy itself, this could have a poor connection or corrosion inside. I would pull it apart and inspect. Before plugging back together I would put some di-electric grease or petroleum jelly in the plug to make a better connection and seal out the moisture.

Peace

[Polar Bear]

I cleaned every connection etc I could find today, and she fired right up,but of course she was inside the garage. Drove her outside for the night, we'll see tomorrow what happens.

btw, what did I manage to poke "right", since the economy light turned red ( cold engine). it's been green all the time, no matter what, ever since I bought her. It get's the readings from the vacuum somewhere I guess.. but where? and where's the wiring connection. I didn't find that out from FSM.

[Petros]

there should be no hole in the distributor cap, it should be replaced. there should also be no play in the distributor shaft (rotational play is normal, for the mechanical advance, but there should be no side to side movement of the shaft). If it has side to side play than the distributor bearings are shot, it will never run properly because the timing jumps around and it could damage the coil pick-up since the gap is very small. It could also allow oil and oil vapor into the distributor since the seal will be damaged from the wiggle in the shaft.

you can either rebuilt the distributor yourself (not too difficult, there is a thread on the topic over in the repair guides section), or replace it with a good used one from a wrecking yard. I do not recommend buying a rebuilt distributor, many of junk out of the box and not worth the money, the used factory distributors from the wrecking yard are far more reliable than the re-manufactured distributors. There is a procedure for replacing the distributor also in the repair guides section, it is not difficult but if you do not follow it the car will not start. important to get the distributor in correctly. also, with the distributor out you might also replace the oil o-ring on it to prevent leaks.

good luck.

[dlb]

btw, what did I manage to poke "right", since the economy light turned red ( cold engine). it's been green all the time, no matter what, ever since I bought her. It get's the readings from the vacuum somewhere I guess.. but where? and where's the wiring connection. I didn't find that out from FSM.

PB, could you take a picture of this 'economy light'? i've never heard of it and wonder what it is. i wonder if it might be some sort of european option we didn't see here.

[TURTCEL]

Yeah I am intrigued by this "economy light" as well.

Peace