Killobat

I just purchased a 1988 RX7 from my neighbor. He stored it in his garage 20 years ago. Before storage, he put in new oil and coolant, dripped oil into the spark plug holes to help "pickle" the seals, and drained the fuel system. Engine has 65,000 miles. I am going to describe everything I have done since purchasing it.


I have drained and refilled the oil and coolant, added a little bit of MMO into the sparkplug holes and then turned the engine over by hand. It turned smoothly without feeling like it was stuck or sticking at all. Put in fresh gas and confirmed that it is flowing at least to the front fuel filter.

So then I went to start it. I had my foot on the clutch and turned the key. Cranked for several seconds, and then fired up. Was running smooth for about 30 seconds. This is when I realized that I was still holding the clutch in, so I confirmed the transmission was in neutral and let out the clutch. This is when the car died. I assume it was just a coincidence in timing with my letting off the clutch. But now it will not start. It cranks and kind of spudders occasionally like it's about to start but doesn't. I have tried throttle open and closed, it spudders more while holding throttle open. I was thinking maybe it was a fuel issue, but then I had a friend spray a bit of starter fluid in the throttle body and it did nothing different. Took the plugs out to inspect and they didn't look fouled (although they are the 20+ year old plugs, I have new ones on the way). Then I turned the motor by hand, listening for the compression release as it passes the plug holes. All 6 sounded the same which makes me think it's not an issue with the apex seals.


I'm not sure what else to try. I'm pretty new at working on my own cars so maybe I'm missing something obvious. I feel like spark plugs are not the issue since it was running fine for 30 seconds however I think I should replace them anyways. But I would like ideas of other things to try afterwards.

Brrraaap

I would check for spark, remove the plugs put them back in their wires and set them somewhere they will be grounded, then crank the car over and have someone look for spark.<br />

diabolical1

iTrader: (3)

welcome to the board.

check the fuel filter, and confirm that fuel is making it to the engine.

Killobat

Did this today and confirmed I am getting spark

Was going to try this today by removing one of the return lines. However I had a struggle with the 30 year old lines and then ran out of time for the day

Brrraaap

If you have spark and compression, It should make some noise on starter fluid.
The fuel pump on the rx7 does not turn on unless the engine is cranking or running. If you want to test the fuel system you can either crank the car, or there is a 2 pin yellow connector kind of behind the inside corner of the airbox down in the engine bay that will make the pump run whenever the key is on if you connect the 2 leads. I would open up the airbox too and make sure there isnt a big mouse nest in there as there was one in mine.

Killobat

I've already used that yellow connector. Made sure fuel was able to get to the filter since that hose was already disconnected. And when the pump is running, I do hear a sound around the front of the car. Which I assume is just the fuel flowing through the system. But I wanted to pull the return to verify. And i have already checked that the airbox and intake are clear.

Maybe there was gunk and other stuff from sitting in the housings that didn't burn off in the those 30 seconds of running? And when it started diluting the mixture too much? Not that it's cleared out, maybe it'll start.

Brrraaap

Well let us know if it starts next time you try

Killobat

Alright, still no start. I'm gonna list out everything I have checked just as a recap:

- Replaced and verified fuel pump is working
- Verified fuel is making it through the system by disconnecting the return line at the tank
- Verified spark by pulling out plugs and watching them spark against metal
- Replaced spark plugs just in case
- A spare ECU came with the car, so I swapped that out
- Intake tube is clear
- Turned over engine with plugs out to flush out anything in the housings.
- Verified that each rotor has 3 equal sounding pulses

Now I am leaning towards clogged injectors (which I am dreading having to get to the primaries). While turning over the engine with the plugs our, I places a towel by the shock tower, where I assume the fuel mixture should have shot out and landed. After cranking it for 5 seconds with the gas petal not pushed, and then floored, the towel was dry. So I feel like that means there's barely any fuel being injected. I know there is at lease a little bit, because when I put in the new plugs, tried to start, and then took the plugs back out, they were slightly wet and smelled like gas. But if it's the injectors, then why wouldn't it start with starting fluid? I'm at a loss.

I'm attaching a couple videos. One is cranking the car with the top 2 plugs removed, as I assume you should be able to visually see at least a mist coming out of the holes, which there is not (sorry it's so short). And the other video is just showing what it sounds like while trying to start. You can hear it sputter on and off.

Is going to be pouring all weekend, so I won't be able to get back to it until Monday. So give me all your ideas

Brrraaap

That's kinda how my car sounded when I had one working injector. Im not sure about series 4 cars (what yours is btw) but I know series 5 cars don't inject any fuel if you crank with it floored as an anti-flooding measure.
Are you sure your plug wires are on right? Each coil will say either L1, L2, T1, or T2 on them. T is top and L is lower, 1 is the front rotor and 2 is the rear rotor.
How are you giving it the starting fluid, right in the throttle body or in the airbox? Is it actual starting fluid or brake cleaner?
If you do end up pulling the primary injectors I would replace all the vacum lines, just take your time and take lots of pictures.

Killobat

Mine is an s4 (1988). The thing is, it almost sounds like it sputters more with it floored. But that safety would make sense.
I am sure the plug wires are correct. I went a head and labeled the boots so I don't have to trace them back every time
It's actual starting fluid. I am spraying it right at the throttle body for max 3 seconds, the running back and trying to start it. I assume that would be enough? Or do I really need someone spraying it at the same time that I am trying to start it?

diabolical1

iTrader: (3)

probably better to have someone spray while cranking. it will have no real way of getting to the other chambers without the rotors actually moving.

i know you said you confirmed spark, but another thing is you should try to get an idea of where the timing is.

Killobat

Alright update:
I changed nothing since Thursday when I last stopped working on it. Decided to just try and start it cause maybe by some miracle it would work. And it did start! For about 1 second before dying again. And then back to the same thing. I took out the plugs, dried them off. Turned over the motor with them out to clear out the housing. Reinstalled the plugs and tried to start again. And now it will consistently start and immediately die like in the video. I had a friend start it and I sprayed a little starter fluid during that 1 second, and each spray would rev it up. And I could have kept it going, but I know too much starter fluid is bad so I only did 3 sprays. I feel like this even more solidifies that it's not getting fuel. It gets just enough to ignite and start but then can't keep up. Unless anyone has any other thoughts.

I plan to start taking about the intake manifold to get the injectors out tomorrow. What's the best way to clean them? I've heard soaking them in carb cleaner, and then maybe getting air and blowing them out backwards. Would that work? Is there another way I should do it?

Brrraaap

It definetly sounds like a fuel issue, there are a few ways people clean them. Keep in mind the injectors are sensitive so any attempts to trigger them should be done with a 9 volt battery. Mine were fixed by a long soak in diesel fuel but other people have sprayed carb/injector cleaner through them while using the 9v battery to trigger them. Once they are out, you should be able to blow through them and if you trigger it you should be able to feel like youre blowing air out. Besides the injectors it could be a pressure issue, the pump can leak back into the tank before feeding and it will certainly flow but will leak more and more at higher pressure. Your regulator could also be messed up, a fuel pressure test would test for both of these. When I was troubleshooting a fuel issue, I pulled the CAS and spun it with the key on, I couldn't hear the injectors clicking and turns out they were gummed up. If you do that you will have to re time the car.

diabolical1

iTrader: (3)

have you checked for any vacuum leaks?

Killobat

I've checked all the lines I can see from the top. I'll check them as I go when taking off the upper intake manifold

Killobat

So just an update since it's been a few days. I pulled the injectors and got them cleaned the best I can do myself. Decided to order a new pulsation dampener since I heard they're basically ticking time bombs. And since I already had it out, figured why not. Once I get that I'll start reassembling and hope it's fixed. I'll let you know whenever that happens.

Killobat

Ok good news. Got everything put back together and she started up. Had it idling smooth for a couple minutes. See the first video for is sitting at 1500ish rpm. Temp gauge still showing nearly all the way at the bottom.

Once it started to warm up. It started dipping below 1000 rpm. And eventually sputtered out. Now that it is warm, it starts right up, but won't hold the idle. I can keep it alive just barely touching the gas. But as soon as I let off, it starts going down, tries to catch itself, and then dies. See the second video. You think I just need to adjust the idle? Or should I take it down the road and get the RPMs up to clear out any carbon buildup?