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-   1st Generation Specific (1979-1985) (https://www.rx7club.com/1st-generation-specific-1979-1985-18/)
-   -   4k+ ignition break up. (https://www.rx7club.com/1st-generation-specific-1979-1985-18/4k-ignition-break-up-747699/)

dbragg 04-17-08 11:53 PM

well, bwaits and i decided we are going to the sunday event. so youll be seeing us there!! look for my car and his widebody FB

bliffle 04-18-08 09:03 PM

Check voltage appearing at the coils.

I just checked my coil voltages while running:
firewall side screw post: 13.6 v. (Leading and trailing coils)
radiator side screw post: 12.5 v. (Leading and trailing coils)

This is a stock 85SE with 170k that starts instantly and runs smoothly.

Maybe you have corrosion on the battery posts that is causing a voltage drop.

HadaGSL-SE 04-21-08 08:56 AM

No further work done on it. The GF family was down all weekend so all I got to do was seam seal the welds for the rust repair.

I will update once I get some more work on it done. None of the parts stores has any parts in stock for it. (No surprise)

HadaGSL-SE 05-15-08 09:42 PM

So I have beenworking on it some more... Saturday is the rally so tomorrow is the make or break day.

The timing is on. The ignition seems fine. I replaced the fuel filter again and drained the tank. There wasn't much flaking that came out but there were three or four small pieces. The car runs ok but still breaks up most of the time. There wasnt anything noticable in the fuel filter I took out after I broke it open.

I am thinking possibly a weak fuel pump? It looks pretty new but who knows, possibly clogged lines? Or is the tank worse than I thought and I just need to constanly replace filters.

Maybe plug in the ECU out of my other car in?

I am getting pretty much frustrated with this damn car. If it makes the rally I have half a mind to wreck it on the last stage.

-Greg

Kentetsu 05-15-08 09:51 PM

Did you run some Seafoam through the tank? If it is a clogged injector, this may help...

perfect_circle 05-15-08 10:52 PM


Originally Posted by Kentetsu (Post 8195981)
Did you run some Seafoam through the tank? If it is a clogged injector, this may help...


you and your seafoam.


and for the record, i believe that it is an electrical issue, as i know how frustrating it can be when everyone keeps telling you to check things youve already checked/verified. but as far as that is concerned, electrical is my weakest subject, so i cant offer you anything sorry.

Dr Rx 05-16-08 01:11 AM

I have the same flipping problem. It's not only break up (hesitation, stumbling) but it seems just a general loss of power at 4k +. It's like the fuel pump is shutting off. It seems more evident in a turn (hesitation, stumbling) or hitting some bumps.

perfect_circle 05-16-08 01:58 AM

wait a minute, i remember a problem that the second gens that had to do with bad grounds(happenned right at 3800 rpm's as well), maybe you should go through and check your grounds.....worth a shot...right?

HadaGSL-SE 05-16-08 08:17 AM

I've checked and cleaned the grounds that I can think of and find. Anyone have locations for them on an SE?

bstrange99 05-16-08 09:26 AM

Check the condition of your alternator and belt. If the alternator stops producing adequate voltage in the upper rpm ranges it won't produce a good spark.

bstrange99 05-16-08 09:29 AM

Oh yeah. The battery too. Start with the basic stuff....All connections and condition of the charging system, including the starter.

Siraniko 05-16-08 09:49 AM

Unfortunately, I have to disagree with most of the above posts. If it starts and runs fine til about 4k, then the system is fine. Change your spark plug wires.

HadaGSL-SE 05-16-08 12:32 PM

I replaced the wires with the ones from my blue car which before the motor blew where known working. I figure the alternator would be alright since it does OK otherwise.

bliffle 05-16-08 01:41 PM

I had a problem like that a couple years ago that turned out to be a high-tension wire that was not seated properly. I coulda swore that all the wires were well seated. I woulda bet money on it. But, nevertheless, a high-tension was loose and when I removed and double-checked them all it went away.

Some garages have an oscilloscope that you can hookup that will verify the firing and voltage level of the high-tension system.

Dr Rx 05-16-08 01:56 PM


Originally Posted by bliffle (Post 8197800)
I had a problem like that a couple years ago that turned out to be a high-tension wire that was not seated properly. I coulda swore that all the wires were well seated. I woulda bet money on it. But, nevertheless, a high-tension was loose and when I removed and double-checked them all it went away.

Some garages have an oscilloscope that you can hookup that will verify the firing and voltage level of the high-tension system.

Which wire is that???

bliffle 05-16-08 05:23 PM

The high voltage wires leading from the coils to the distributor (2) and from the distributor to the plugs (4).

The autostore has some electrical gel that claims to improve those contacts, but I've never tried it.

HadaGSL-SE 05-16-08 08:16 PM

Plugged in my good ECU, no difference. Seafoam, no difference.

Looks like im running my co-workers neon...

perfect_circle 05-17-08 12:04 AM

you could always just race in third.

Crit 05-17-08 01:06 AM

I beat the same problem, and my ignition was dead on.... according to the pulley. If the car hasn't run right since you've owned it, realize that you can trust nothing. My pulley was 90-deg off, and exhibited the same symptoms yours did. It fell on its face around 4k, and if you were persistent you could barely floor it to 6k if you had the balls to stay in 1st gear.

If you think you might have the same problem, turn the dizzy 3 or 4 teeth to each side of the locating divot at TDC, and see if it magically improves. If you're 1/8th of a turn out and it clears up, it's because your pulley is 1/4 turn out. Try it, and if it works you'll kick yourself.

Trust nothing.

HadaGSL-SE 05-18-08 11:44 AM

Well it didn't run for the rally but I did get to run my co-workers neon.

I don't think I have ever had that much fun in a car and certainly not in a neon. It wasn't really a rally cross so much as a rally sprint. Since the co-worker doesn't care about the car we were bouncing of the dirt berms and generally having a ball. I was mid pack overall and toward the top of the stock 2wd class when the co-worker hit a berm head on and ripped off his oil filter ending our day. I only would have gotten one more run so it wasn't a big deal.

I will definetly check the distributor now that I have more time. I don' see how it could get clocked wrong with all the vacum advance stuff on it. It's a pretty tight fit.

Thanks so far!

-Greg

Crit 05-18-08 04:33 PM

No Greg, the issue is that your front pulley might be turned 90 so that when you time your dizzy and stab it, it isn't really where you think it is. Even though everything looks right, it's internally out of phase. Basically, when you line up on the timing mark your front rotor isn't really at TDC like it should be. Try moving 3 or 4 teeth to either side to see if it clears up.

Granted, this is only if you've either had the pulley off or if the car's never run right since you've owned it. If it used to run fine, then the pulley hasn't just up and turned on you.

Dr Rx 05-18-08 08:12 PM

Mine is fixed..... I replaced the fuel filter with a gsl-se filter and a new gas cap that actually seals now :) Runs like a top!


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