GT runs like crap

[greensmurf20]

posted in open discussion depending on where this goes "fuel", "electrical", "mehcanical", never know on a post like this so here it is.

GT has been running fine for the most part, other than my exhaust leak that sounds like crap also. today it died just as i got about a mile away from home, took the cap off, blew the points out and threw the cap back on and it was good to go, done this 2 or 3 times since i've been driving it. get to where i'm going, 6 or 7 hours later i "attempt" to leave and the car is just running horrably. pulled the carb, the baseplate gaskets were good still, can't find any vacuum leaks, dwell is fine, the blacksheep uncle has the timinglight, but it fires right up when you bump the key so i would assume its close. it just dies as soon as it starts, and when you keep it running it usually wont run under 1,500 or 2,000. trying to go down the road it spits and sputters, misses until you just stomp your foot down for a second or two and once it start to pick RPM up it acts fine, does real good above 5K, but anything below is just ungodly bad. i know it really isnt much to work from, but i'm pointing finger at ignition or carb since it started the way it did today and since it does fine in high RPM, but can't do anything but fall on its face and come next to dying with anything less. anything obvious to check?

[kwilford]

Originally Posted by greensmurf20 posted in open discussion depending on where this goes "fuel", "electrical", "mechanical", never know on a post like this so here it is.

I'll park this in the "Tuneup" section until we figure out the problem. But the "Discussion" section works fine to start, as I usually move threads when I see where they end up.

Hmm, sounds a bit like ignition, but it's hard to tell from here. Next time it dies, before you do anything else, try unplugging the coil wire from the top of the cap, and hold it about 3/16 of an inch from the block, and get someone to crank it over (or use one of those cheap starter jumper buttons and do it yourself; I used to carry one with me when I was having problems). If you get a good spark (or you get a good shock!), that eliminates problems up to the coil. If not, a new set of points and condenser is reasonably cheap, and then you have a spare set. A bad coil is more rare, but possible. If you have good spark at the coil, that still leaves the cap, rotor, plug wires and the plugs themselves. Solving that is usually by trial and elimination. Start with a new rotor, then a cap. If you have a Volt/Ohm meter, check the resistance in the plug wires. They should be less than 10,000 ohms. Finally, try changing the plugs.

Or, it could be fuel related. Sounds like a Solex to me

[First opel 1981]

I used to get the same problem in my gt. Turns out it was where i was getting my gas. I am not kidding!!! When I bought gas at a particular 76 station, my car just wouldn't run. If I got gas most anywhere else, it would run great.

[greensmurf20]

yeah ,keith, still got that old solex. supposed to be getting a weber and petronix at vicki and allens, i think new ignition and carb would almost have to eliminate my problems, but i'm very leery of taking it down there now. cap, rotor, and plugs are all bosch and new less than 3,000 miles ago. wires are NOS set, older than the rest but under 6,000 or 7,000 miles. just weird, does fine when i drive there, go to leave and its like this. the sudden change makes me think its something along the lines of coil, something internal in the distributor or that carb...again. i've had problems with the carb before and i'm not sure its not its fault this time. i havent gotten gas since friday so i would think it would start running bad soon after, altho i know my GT is picky on where i get gas. theres only 2 citgo stations or a sonoco station that i'll get gas from, anywhere else my gas mileage goes down 5-10 MPG. usually get 25MPG on average. i got about 3/4 tank. i dont have any other carbs, so i'm going to start off like keith said, testing igniton stuff. starting with coil and then off to the points and condenser, already have spares. gots to go to work first, keep you all posted on my findings when i get home, and thanks for the inputs.

[GTJIM]

Try popping the hood after dark and watching for stray HT electrical discharges when the motor is running. Sometime the HT electrical leaks can be seen as blue sparks "dancing" over the cap/leads or plugs at night.

[Dmcbrass]

It sounds like you haven't checked the timing yet. I would start there. Also make sure the dwell is correct. Watch the dwell while the engine is run through its rpm range. The dwell shouldn't move more than 3 degrees from 1000 to 4000 rpm. Also make sure that the centrifugal and vacuum advances are working correctly.

[Old Hippie]

G.Smurf, part where you "blow out" the cap, do you see moisture in there? If there is a condensation problem from cooling, try using a bead of rtv on the bottom of the cap. Just a quick water fix from my Ford Falcon days.

[calvin]

Ditto on the spark in the dark check the dist. cap especially. Also toss some HEP into your tank it is very cheap (under a buck) and if there is water in there might help. In case the gas is suspect (at least this tankful) try a little octain boost to help this tank.

c

[Scott McDonald]

Let me know & I'll put one together for you.

[Willy_g77]

i had the same problem. I put new points, rotor, cap, and plugs and wires and then it wouldn't die. the i adjusted the screws on the carb and it runs fine now. except for them damn oil leaks, argh!!! i think the point gap is 0.018, can't remember.

[West Coast GT]

Sounds like bad gas to me. If you rule everything else out, get some good fuel and top the tank off. Don't add alcohol yet. Later, add fuel additive on your next tank.

[greensmurf20]

well, all day at work i had got to think of what it may have been. i decided i was not gonna check anything else, but just go straight home and rip the solex off and put the other solex off my good running "spare" GT, and it ran a whole lot better, except for my 2 week old bosch super sparg plug had also died. only replaced the bad once since the others are very low mileage. now i can't even get the 72GT with the auto over 40 cuz its spitting and popping and mission so damn bad with that other solex and bad plug. thank you Scott for the weber offer, but i'm going to ohio for vicki and allens get together and i'm getting a weber, petronix and swaybar there. i think a weber and petronix would really help the reliability of my car. swaybar would just be a nice goodie i dont really need. my timing should be fine, was set less than 2 months ago and the dizzy is still tight. so i hear ya ketih, sounds like solex, a brand freaking new rebuilt solex that can't stay running. i hate this paticular solex, never beena good carb, even after the rebuild. so if GT runs like crap for no apparent reason after you go to start it, ditch the solex if your dumb enough like me to run GTs for 3 years on them things!!!

[Dmcbrass]

Hope your're right about the solex. But my bet is on ignition or timing. Have you ever checked the valve timing?

[Jeff Pozorski]

Check and make sure the condenser is properly grounded on the side of the distributor. The mounting screw will sometimes loosen up allowing intermittent grounding which will make the car run like crap until it "grounds" itself again. My first Manta behaved just like yours is doing now and all it took to fix it was tighten up the condenser screw!

[Jeff Pozorski]

A great rule of thumb to remember with our cars is that when a problem is intermittent it is most ALWAYS often a poor ground somewhere. When Greensmurf took off the dist. cap and blew it out that could have been enough to jostle the condenser back into a good "ground" again. Timing will very rarely go bad and then go good again at the drop of a hat. If the distributor is loose, causing the timing to change at will the car, it is extremely unlikely that it would swing between good and horrible. It would more than likely go from good to bad to non-running and that is not the case here. He also mentions a bad oil leak which will also worsen a poor ground situation. Always look for the simple things with Opels before considering the more difficult ones.

[opelenvy]

I had a Pathfinder with the same problem. It was the main coil wire to the center of the distributer. At low RPM's there was low current flow and the spark was barely making it through. Once you raised up the RPM's the current flowed better and the bad wire didn't make a difference. Taking off the dist. cap definitely moves that wire and might help with the intermittent problem. It took two Nissan dealerships two days to figure it out. They kept looking at the FI. They cleaned the injectors about 4 times. I didn't pay for that.
check wires. When it's running like crap wiggle wires and check for change. You could also pull of one spark plug wire at a time and check for change.

[greensmurf20]

i know the car dies once in a while because it gets a chunk of dust or whatnot in it once in a while, i blow the dizzy out once in a while but it keeps working dirt from the bottom up to the top. i know thats the cause of it dying, everytime it dies it has a spec of dust or dirt between the contacts. the running ****ty problem was a new problem that hadnt occured yet, except for all the other times my solex carb was messing up so i finally rebuilt it and it was fine until 2-3 weeks ago, the primary jet about fell out and the choke housing was a little loose. fixed that and the carb was still never really right, but still ran good. i switched the carbs on my GTs. carb on white car to carb on yellow car, yellow cars carb now on my car. my car runs great, and the yellow car now inherited the same charactaristics as mine had, its got an auto trans and i can't even get it above 40!!! i'm thinking i'll tear the dizzy guts out to clean it really good and then put it back together, did it before with my other distributor and it worked well afterwords. thanks for everybodies input.

[Old Hippie]

Jared, when you take your dist apart, take the bearings and seals to a parts house and get new ones. Something I do to my dist cap (my dirt/mud road truck) is this: 1) seal the bottom w/ RTV or 2) make a grove in the bottom w/ a dremel and glue in a rubber o-ring for a seal. The o-rings cost about $.50 at the hardware store (like ACE), so it's cheap to cut it to fit. Just takes alittle time to make the groove. It's well worth it though, especially on really wet roads driving a "points" car.
Barry

[greensmurf20]

"It's well worth it though, especially on really wet roads driving a "points" car."

she'll be "petronixed" next weekend, and "weberized" the same day. gone 400 miles with the replacement carb and its doing great, never gone 400 miles without some sort of carb trouble.