Timing or Ignition issue

[SynthOkami]

Hey guys, so since I bought my 85 GTS, I've been having issues with low power, hard to start, and I can't keep my ignition timing where it needs to be in order for it to run properly. I've replaces plugs, distributor cap, and button, I've replaced plug wires, battery, alternator, (which some of these parts were needed before this issue) and full clutch assembly. I know the clutch just needed to be changed and went out on me. But I can't figure out why I have to keep advancing the timing for it to run "properly". It still misfires and is very low on power. But I have a suspicion that it might be my ignition coil. It's the original 1985 coil, and I don't know if that would for sure cause the issues I'm having specifically. Something that may also be unrelated but might be handy to know is that I did a compression check and everything was 160-170 with minimal change. So I'd like to hear from you guys to get some answers possibly. Thanks!!   

[sirdan]

In my experience coils 99% of the time either work or don't work so I'm doubtful a new coil would fix the issue. Is the bolt loose enough that you can adjust it by hand? I've had the bolt be not tight enough and it would slowly turn on me. Check your voltage at the coil low voltage will cause weak spark. It is also becoming more and more common for new parts to be junk out of the box so it might be worth looking at the new stuff.

[SynthOkami]

The distributor isn't moving. I've advanced it to make it run better. But that was after a lot of work being done and my dad didn't want to help me mess with it anymore. But I'm going to try putting the timing at 0 and adjusting the idle control be to where it's supposed to be, instead of it being super advanced. All the parts I've put on have been NGK, NGK V-Power plugs, and an Exedy clutch assembly. The only cheap part I have on it is the alternator. It's just an autozone one, but it's putting out 12-13 volts. So that's not the issue. I'll check the coil, and put the timing where it should be and see what it does. Something I also forgot to mention, was we checked the timing chain marks and they're good. Previous owner put a new timing and water pump kit in, and everything looks really new.

[danf]

Have you triple-checked the firing order (seeing as you said you replaced the plug wires?) If you get a few of those wrong it may start on one cylinder but it sure won't be too happy about it and most likely not want to stay running.

Pull the cap and manually find TDC and make sure the rotor is pointing to the #1 cylinder on the cap. Then make sure the firing order is correct... that's about all I can think of.

When the coil goes it usually goes completely like sirdan said... however when the coil gets hot it can malfunction. As you can't get the car running long enough to warm up I doubt that's the issue. Have you checked the oil for fuel in it?

[SynthOkami]

All good on oil and fuel. I changed the oil and filter while I was doing all this, and drove up and filled it up with fresh fuel. So that shouldn't be it. But I checked the cap, and the rotor is at #1 when at TDC (0 degrees). And all the plug wires are correct. I guess I'll try to explain really poorly how the car is setup to run right now. The timing chain timing is like this, the crank pulley is set to 0 degrees (or 12 o'clock), and the cam pin thing is set to 12 o'clock. I'm going by the pin set thing on the cam, not by the dot on the cam gear. I heard that needs to be to the left and the pin at 12 so that's where it's at. Then, the distributor rotor is on 1#, and it refuses to move the car when it's set to 0 degrees when I check it with a timing light. So I moved the distributor to advanced 5 degrees and it's slightly better. The only ignition timing the engine seems to like is like not even on the scale on the crank pulley guide thing. from 0 it's advanced like maybe 20-25 degrees, and that's the best it runs, and it still barely moves the car at times. And other times it feels almost normal. So with it acting crazy and being fine one minute and gasping the next it can't be the timing chain because it's in the same position. And so is the distributor too. SOOOO me and my dad are pretty lost as to what it could be.

But thanks you guys so much for helping out. As ignorant as it sounds, I'm 19 and this car's my daily right now. The Miata I daily drove needed the engine rebuilt right after I bought this car so I'm stuck trying to get this thing running.

[danf]

I was more thinking of the possibility of a stuck injector and fuel leaking past the rings into the oil pan.

Back to the timing issue, has it always run like this? It is possible that the distributor is a tooth off when it was installed, either that or the distributor itself was not seated down all the way when installed. However, the rotor would not exactly be on #1 but a bit off degree wise. I can tell you from experience if you're a tooth off when installing the distributor it runs like crap. 

[SynthOkami]

Not to this extent. I drove it for about 3 months, and it just was kinda driving. Like, it seemed like there was a slight something wrong but not much. So that's when I started replacing old parts, and it ran better. Then, slowly it started to kinda lose it. But there's always been a very small misfire. But the compression is great, so I just thought it'd be something simple.

My dad wanted to take apart the top and front of the engine to look at the chain and see where it was first, so we took the distributor out and put it back to where it needed to be. We checked because we put it too far one tooth, and then put it two teeth back to make sure the one in the middle was #1.

[danf]

Hmm. If the timing is still jumping around, have you inspected the harmonic balancer? Maybe it spun around and if it did the timing marks would literally be all over the place.

Edit, to check this find mechanical TDC and confirm it with the valve rockers on #1 (they should be loose at TDC.) When that's done, the timing mark on the harmonic balancer should line up at 0 degrees. If it doesn't chances are the harmonic balancer is toast. If I remember right, pre-1985 were solid balancers but 85 and up are not.

[SynthOkami]

Oh my God I didn't remember until now. The key that keeps the pulley on the crank is loose. it moves around slightly because it's worn. I was wondering if that was an issue but we didn't really think it could be that bad of an issue.

It's this part, and it wiggles inside that spot. This is a picture of a damaged one. Mine doesn't look nearly that bad.

[danf]

If the harmonic balancer can move around, that's going to make it super hard to set the timing.

The 85 and up balancers are not solid iirc (they have either a rubber or fluid filled? can't remember - coupling between the inner hub and outer pulley) and when these fail the harmonic balancer can turn and the timing marks will be off.

When it's running can you see if the harmonic balancer is wobbling? That's a sure sign of it failing or failed. If it's really bad you might be able to turn the alternator or power steering pulley. If either of those move without turning the centre hub on the crankshaft the balancer is bad.

Edit: You are jumping the check connector before setting the timing, correct? If you don't the ECU will be trying to correct the timing you are trying to set...

[SynthOkami]

I just talked with my dad because he was the one who was messing with the timing chain and pulleys, and he said that everything was fine with the harmonic balancer, he checked for play and it felt solid and looked fine. I just tested trying to turn the accessory belts and nothing moved. But I thought i jumped them, but I guess I'm second guessing myself. Which SPECIFIC connector do you have to jump?

[danf]

Sorry, hectic few days.

Without having a picture handy, there's a two pin connector by the air flow meter. If I am remembering correctly there's two connectors there, you want the connector that has the pins running parallel to each other. There's another one that has one of the tabs rotated 90 degrees, that's the fuel pump check so don't jump that one.

With the car idling, jump the two pins. You should hear a change in the engine as timing drops down to base timing. If you don't hear this slight change, check your TPS and make sure the IDL pins are shorted when your car is idling - if it isn't it needs to be adjusted. If adjusting it doesn't work the TPS is likely bad and will need to be replaced.