sluggish...ignition issues? plus fuel line question...
#1
sluggish...ignition issues? plus fuel line question...
I have an 85 gs (stock carb and engine) and wanted to see what my issues could be. When in neutral, just idling, I step on the accelerator and when I hit about 4,000 it starts to bog and choke (pedal all the way down). When I let off the pedal (just a touch) it runs fine. Does the same thing under load on the highway, 5th gear, full pedal.
One other issue is backfiring/stumbling when car is taken out of gear and runs down to idle. I've adjusted the idle and fuel mixture 1000 times but to no avail.
The car is slow either way (100 hp stock back in '85 doesnt translate to much now) but I feel that this could be something like a shutter valve, coasting valve, exhaust leak (maybe at manifold?) or possibly the anti afterburn valves.
let me know what you guys think...thanks
One other issue is backfiring/stumbling when car is taken out of gear and runs down to idle. I've adjusted the idle and fuel mixture 1000 times but to no avail.
The car is slow either way (100 hp stock back in '85 doesnt translate to much now) but I feel that this could be something like a shutter valve, coasting valve, exhaust leak (maybe at manifold?) or possibly the anti afterburn valves.
let me know what you guys think...thanks
#4
Lives on the Forum
Those stock filters are good for about 5 - 10k miles, depending on the quality of gas and the condition of your tank and lines. Definitely start there.
You can verify the position of the shutter valve by looking at the position of the arm below the carb (driver's side). Not sure which position is open though. But once you figure that out, you can even wire it open for testing purposes.
If that doesn't clear up things, then consider rebuilding the carb.
.
You can verify the position of the shutter valve by looking at the position of the arm below the carb (driver's side). Not sure which position is open though. But once you figure that out, you can even wire it open for testing purposes.
If that doesn't clear up things, then consider rebuilding the carb.
.
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#11
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for further clarification
Looking at the carb from the driver's side.
LEFT LINE (smaller of the two) is your RETURN (has a check valve in it, if not, it has been removed and ya might want to put it back if your running stock nikki).
RIGHT LINE (larger of the two) is your SUPPLY line.
Hope that helps
LEFT LINE (smaller of the two) is your RETURN (has a check valve in it, if not, it has been removed and ya might want to put it back if your running stock nikki).
RIGHT LINE (larger of the two) is your SUPPLY line.
Hope that helps
#13
An eventful day it was today. Changed the fuel filter, added a 2nd filter near the carb, ran the car for about 15 minutes (got a few miles down the highway) and then lost 50% of what little power I had.....
I figured it was yet another cheap coil gone bad (recently bought factory one to replace a bad one 3 days ago) seeing as how all of a sudden at idle the car was running at about 400 rpm. I unplugged the old coil and this did ABSOLUTELY NOTHING...so either those 2 plugs are shot or its the coil. Limped back on two plugs (surprised I made it) and put in a freshly bought coil....didn't fix the problem much. Changing the plugs tomorrow along with wires.
Told the woman that if I have to replace one more coil or spark plug with this car I will just have to use it for storage (5th and 6th coil and will now be my 5th set of plugs in 3.5 years).
Added bonus for the day...all kinds of smoke coming out by the manifold....at least I know where my backfiring problem is coming from. Has to be unspent gas cuz the plugs are'nt firing.....what a day.
carb has been adjusted real nice....and will be again after plug change...so thats not whats causing my ignition issues.
I figured it was yet another cheap coil gone bad (recently bought factory one to replace a bad one 3 days ago) seeing as how all of a sudden at idle the car was running at about 400 rpm. I unplugged the old coil and this did ABSOLUTELY NOTHING...so either those 2 plugs are shot or its the coil. Limped back on two plugs (surprised I made it) and put in a freshly bought coil....didn't fix the problem much. Changing the plugs tomorrow along with wires.
Told the woman that if I have to replace one more coil or spark plug with this car I will just have to use it for storage (5th and 6th coil and will now be my 5th set of plugs in 3.5 years).
Added bonus for the day...all kinds of smoke coming out by the manifold....at least I know where my backfiring problem is coming from. Has to be unspent gas cuz the plugs are'nt firing.....what a day.
carb has been adjusted real nice....and will be again after plug change...so thats not whats causing my ignition issues.
#14
Ignition? issues
85 gs carbureted...relatively stock. Replaced faulty coil 3 days ago and took the car about 60 miles round trip no problems.
Yesterday...about 5 miles down the road I lost a good amount of engine power...could barely do 50 on the highway and VERY slow when accelerating. So I replaced the other coil, ran it a bit...and the new coil cleaned up the plugs pretty good so I took it out again. 2 miles later something let go and the same problem again.
Maybe a ground for the coils? Maybe a bad plug wire? All I know is I have 4 new plugs and 2 new coils and it seems only one wants to fire at a time.
I'm on my 3rd set of coils and 4th set of plugs in 3.5 years....something is amiss. Any suggestions are helpful...thanks guys
Yesterday...about 5 miles down the road I lost a good amount of engine power...could barely do 50 on the highway and VERY slow when accelerating. So I replaced the other coil, ran it a bit...and the new coil cleaned up the plugs pretty good so I took it out again. 2 miles later something let go and the same problem again.
Maybe a ground for the coils? Maybe a bad plug wire? All I know is I have 4 new plugs and 2 new coils and it seems only one wants to fire at a time.
I'm on my 3rd set of coils and 4th set of plugs in 3.5 years....something is amiss. Any suggestions are helpful...thanks guys
#17
I was able to locate them. I am going to test both of them tomorrow. As for reference, is it worth it to buy new ones or better off with GOOD used ones? For example, $90 used and $160-$190 new. Seems to me that it would be worth it to buy used, maybe even a spare set.
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Frisky Arab
2nd Generation Specific (1986-1992)
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08-18-15 05:30 PM