3rd gen starts when cold but no crank when warm
10-29-17, 12:01 PM
#1
3rd gen starts when cold but no crank when warm
So my rx7 starts when cold but when warmed up wont crank. When warm up i can by pass the starter by push starting the car and it starts and runs. I tried a few things like checking battery, changing starter, checking connections to battery and starter. I am stuck what else should i do
10-29-17, 02:19 PM
#2
Super Moderator
iTrader: (1)
When you say it will not crank once the car is warm, what do you mean? Do you hear the starter engage and turn the flywheel? Or when you turn the key to start the car you hear a "click" or no sounds at all?
10-29-17, 03:05 PM
#4
Super Moderator
iTrader: (1)
There could be some computer logic malfunction and/or starter may be degraded. Have you pulled the starter to have it tested? Have you looked at the clutch switch? The factory alarm (in Body CPU) may also be a failure point. Have you noticed any other unusual electrical problems, such as locking the car, factory alarm arming/disarming?
10-29-17, 03:10 PM
#5
Cpu is a microtech and the starter is good. As far as the security system it is factory. I tried the clutch switch by bypassing it and it still would not crank. What gets me is it only does it when its warmed up. If it sits it will start with no hesitation. If it is cold it wont evwn crank.
10-29-17, 03:19 PM
#6
Super Moderator
iTrader: (1)
The microtech is an aftermarket ECU (Engine Control Unit) or PCM (Powertrain Control Module). The Body CPU controls all the ancillary electronics on the car like turn signals, door locks, alarm, etc...
Last edited by Gen2n3; 10-29-17 at 03:21 PM. Reason: mistaken double post.
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10-29-17, 03:32 PM
#8
10-29-17, 04:48 PM
#12
https://www.rx7club.com/3rd-generati...-relay-872841/
After sifting through the above thread, locate the security relay (H302) inside the left side kick panel. Disconnect the connector, and jump the two largest wires on the connector. If this action solves your starting issues, you likely have a bad CPU#2. At that point, you can either get a new one for about $250 or simply live with the jumper fix as most on the forum generally do.
Hope this info helps!
After sifting through the above thread, locate the security relay (H302) inside the left side kick panel. Disconnect the connector, and jump the two largest wires on the connector. If this action solves your starting issues, you likely have a bad CPU#2. At that point, you can either get a new one for about $250 or simply live with the jumper fix as most on the forum generally do.
Hope this info helps!
10-29-17, 04:50 PM
#13
RX-7 Bad Ass
iTrader: (55)
If you turn the key and nothing, it's either the wire that's going to the starter that tells it to turn over and that circuit or the starter. Plain and simple.
Read the click-click-start threads, that points to a lot of the troubleshooting. Also, if you have a situation where it won't start when hot, jack up the car and put a meter on the small wire going to the starter. Have someone else turn the key. With the key to On, you should see 12v on that wire. If you don't, it's something in that circuit - the clutch switch, the security relay, something. If you do see 12v, it's something with the starter.
Dale
Read the click-click-start threads, that points to a lot of the troubleshooting. Also, if you have a situation where it won't start when hot, jack up the car and put a meter on the small wire going to the starter. Have someone else turn the key. With the key to On, you should see 12v on that wire. If you don't, it's something in that circuit - the clutch switch, the security relay, something. If you do see 12v, it's something with the starter.
Dale
10-29-17, 05:04 PM
#14
Going to try that. I read a lot of the threads on the click click situations. I wish i got a click click but my car either starts or i dont get anything at all. Not even a click. Thought it may be one of those common rx7 problems but i see its not. Going to take the starter out and just make sure i did not put the original starter back in. Both starters are jdm.
10-29-17, 05:31 PM
#16
Jumping the H302 relay is the easiest thing you could do on your own. I'm the least DIYer on this forum, yet I was able to jump the relay with ease. Still, I always had in the back of my mind a sure-fire permanent fix; hence, replaced CPU#2 eventually.
Good luck, friend!
Good luck, friend!
Last edited by Topolino; 10-29-17 at 05:42 PM.
10-30-17, 07:53 PM
#17
Update
Pulled the starter and had it tested again. Starter is good put it back in and started the car three times. Started with no issues. I let it warm up and bang no crank. I dont know if this is related but my coolant buzzer is going off and the car is not overheating or needing oil or coolant. Wondering if it is a safety if the buzzer has gone off you cant start the car
10-30-17, 10:35 PM
#18
https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.rx7club.com/new-member-rx-7-technical-256/add-coolant-warning-buzzer-even-though-coolant-reservoir-full-914328/&ved=0ahUKEwjBgNn39JnXAhVr5oMKHVWSDDIQFggcMAA&usg= AOvVaw2-Pm_YUw6VlOoodfCvILAx
10-31-17, 07:59 AM
#20
RX-7 Bad Ass
iTrader: (55)
There's no "low coolant car won't start" circuit. It's all in the shop manual - ignition key to clutch switch, to security relay, to starter.
It's either that circuit, the starter, or the battery/battery cable going to the starter. That's it.
Dale
It's either that circuit, the starter, or the battery/battery cable going to the starter. That's it.
Dale
10-31-17, 10:20 AM
#22
Super Moderator
iTrader: (1)
In line with Dale's recommendation and advice on the starting circuit, verify that the ground cable is firmly connected to the battery and the chassis. Also ensure there are no corrosive buildups, kinks, or breaks along this cable. I would also advise that you verify the condition of the Positive cable to the starter, again looking for kinks, breaks, or corrosive buildups. Please disconnect/remove the battery when verifying these cables as it will provide a "shocking" experience!
11-02-17, 11:07 PM
#25
Topolino diagnosed your car on 10/29. It sounds like the security relay went bad, which happens to every single FD sooner or later, and won’t allow the car to start after it overheats. Jump the two thickest wires and you’ll never have this problem again. I had to do mine just a week ago. Stop making it harder for yourself by uninstalling your starter again. The starter is good.
Nick
Nick