Hello all.... I own a 93 rx7. When I had the engine rebuilt all was fine for a while but now the car wont start when the engine is at full temperature. So at the minute I cant even go to the petrol station with fear of not been able to start when I come to leave. Once the engine is cold again she will start first time. The car has been off the road and garaged up for nearly 2 years due to spending money on a new house but when I was last at WGT Pip said the compression seems lower than normal and he thinks he needs to have a look inside as another rebuild may be looming. Pretty annoying when the new engine has only done 5000 miles. Trusting Pips thoughts I just wondered if anyone maybe has seen this problem before...Cheers.
Sorry to say that yes this is a problem that can occur with a Rotary and I always say to potential buyers to take the car for a run leave it 5 minuites then check that it restarts as Rotarys unlike piston cars at times will not restart when hot due to low compression at times.
One thing you can try is to put hotter plugs in the car as this may well get around the problem for quite a long time.
Hope this helps
cheers clive, will swap them and let you know.
Sounds kinda like low compression as Clive said bud :(
Yup I agree. Had this exactly before I changed my engine. Compression went low and starting was almost impossable when engine was hot - getting petrol was a right pain in the bum! :o
Likewise - had to call the RAC out to a service station due to the same problem :o
Can also be a TPS problem. When the car is hot & running how dose it respond to throttle input? Eg: From idle if you slightly blip the throttle doe it just cut out or will it idle nicely?
Im not saying that its not the compression but its always good to eliminate other things first. I know that when the engine is hot & your TPS is reading a very low voltage it makes it very hard to start the car.
Good luck with it. Hope you get it sorted.
^^ That\'s very true. I had mine mis-aligned at one point and it would stall (OK, not the same, but as said it does have a bearing) as soon as it was warmed up.
Quote from: Dr-Rotor;525000Can also be a TPS problem. When the car is hot & running how dose it respond to throttle input? Eg: From idle if you slightly blip the throttle doe it just cut out or will it idle nicely?
Im not saying that its not the compression but its always good to eliminate other things first. I know that when the engine is hot & your TPS is reading a very low voltage it makes it very hard to start the car.
Good luck with it. Hope you get it sorted.
blipping the throttle from idle has never caused it to cut out , it does idle quite nicely. Not knowing a great deal about engines what is TPS? Thanks for the interest people.
TPS is a Trottle Position Sensor mate, it sits on the throttle controle acrm & tells the ECU how much loud peddle yoou have got on.
Jono
Try a new set of plugs or clean them up if there still ok. Mine were really black when I took them out and after a thorough clean the car starts from hot fine!
had a look and I have 9`s both leading and trailing, where is the best place to get a couple of 7`s?
Haaa...thats half your proplem. You need stock plugs for a stock motor. If you not runing more than 15psi you dont need 9s all round.
It dose make it slightly harder to start cars with cold plugs all round. Some cars seem to be fine & start up first time easy. My monster requires very slight throttle to start...if you try to start it without that little bit of throttle it will not work. HKS racing plugs seem to have that effect..haha. If I put NGK 7 & 9s in it will crank over very easily.
Also I still think you need to check your TPS. Do you have a power FC ECU with the hand controller? It will show you the voltage if you do. The first VTA needs to be between 0.75 & 1.25...with ignition on & engine off but the engine at opperating temp.
If you dont have a PFC...well then I will have to find out how you can check it.
If you would like the full manual for the car on your PC I can email that to you too if you like. Just email me to let me know. bmlove777@hotmail.com
i had a slight idle problem before my engine trouble so i think i will have a look at my tps when it goes back in and check the values on the pfc, i didnt know you could check it on there, thanks for that bit of info dr rotor.
ste, you can get 7\'s from pretty much any where, ebay, or most vendors on here stock them.
No worrys mate!
btw email on its way ;)
Yip, got it. Cheers.
yes I have a power ecu and I will be checking what you mentioned tomorrow, will order some new plugs too. Cheers Dr.
All good mate. I hope it is your TPS & the plugs...better that than a rebuild.
Just had the engine upto full running temp, turned it off and then only put the ignition on the VTA1 was at 0.36v and the the VTA2 at 0.85v, lower than you say it should be.
Also I tried blipping the throttle about 40 times from idol, sometimes the revs drop quick down to around 600 and rise to 900 straight after, sometimes the revs drop to about 1300 and drop slowly to 900. Only once did it cut out when the revs dropped.
I have noticed too that if you start the engine straight after it cuts out/turned off it does tend to start at full temp, if left for 10 seconds and over it will then not start.
Just thought I would give you as much detail as I can for you, cheers for all the help from everyone.
Ordered the hotter plugs last night too but wont be able to fit them until the weekend, as well has a new f100 ecu to cure the electric window and seat belt light problem.... I can see me getting cramp in both arms tyring to change the f100, what a duff place to put it!!
sounds like low compression to me, dont think putting different heat plugs will cure it unless the plugs you have are fduked
Adjust your TPS, put in the new plugs & see what happens.
Email me for the manual on how to adjust the TPS. bmlove777@hotmail.com
It sounds like low compression to me as well, its best to get the compression checked anyway :) I also found that on hot days or when the engine has been running for a while the whole engine bay is rather toasty, if the air filter(s) aren\'t shielded much then it could be sucking in hot air, which on my car make the car idle lower than normal, but it does sound rather like a compression related issue, it might just be low on 1 of the rotor faces
Dr-rotor can u please send me a copy of that manual it may come in handy my email is ricky.jukes@sky.com (ricky.jukes@sky.com) thanks....:wiggle
Just changed the 9 leading plugs for 7`s, she is starting a hell of a lot better now when at temperature! Only had chance to warm her up off the road, will give her a proper run tomorrow, cheers for all the help.
Quote from: jukesr;526324Dr-rotor can u please send me a copy of that manual it may come in handy my email is ricky.jukes@sky.com (ricky.jukes@sky.com) thanks....:wiggle
To all those that I have offered the manual to, Im sorry. I cannot email it. Its over 80mb even compressed in a Zip file.
Soo heres the alternative option. Go to this webpage. Open every section of the manual & save it to your computer.
http://www.fd3s.net/shop_manual.html
Got back from drive yesterday and she was running fine, turned the engine off, waited 5 Min\'s and started her back up but she was coughing and spluttering on idol. Tried again just now and she is still struggling to idol and she cuts out now too on idol...... My friend is going to compression test her next week end..... I\'m thinking low compression has come and bit me in the arse, I cant afford a second rebuild only after 5000 miles.... I\'m gutted.
sorry to here that mate, there is something wrong somewhere if its cutting out and struggling to idle, i wouldn\'t drive it TBH until you get the compression is done just on the off chance it will either gets you stuck or does any more damage.
she is all garaged up going no where mate... she will probably be in there for the next 200 years at this rate....
So did you check or reset the throttle position sensor?
It hasnt really been made clear. I would definately definately do this first before writing the engine off..
Quote from: BenLewisMav;527123So did you check or reset the throttle position sensor?
It hasnt really been made clear. I would definately definately do this first before writing the engine off..
Yea make sure your VTA1 & 2 are all good.
A friend of mine has a VTA2 problem...its high lighted on the PFC and his car will cut out when he comes to a stop and its hot from thrashing it or just driving.
So check your VTA please. Make sure the car is at full temp...85C. Just have ignition on. Check VTA1 is between 0.75 & 1.25...throttle in all the way & check VTA1 goes to 4.8 or so...Must not be high lighted or higher than 5.0.
Check VTA2 should be slightly higher than VTA1 without throttle and not high lighted. Around 1.25 - 1.5. Then throttle in and it should be in the high 4s as per VTA1 and again should never be high lighted.
If ither one is high lighted they are in the wrong voltage range. Download the manual in the link I posted above and study up on how to adjust them.
Since your car now starts and has the right plugs in it and drives fine I think its just a throttle and idle problem. If it had low compression your power and just general driving around would feel like crap. Also it would strugle to start from cold as the compresson is low and would idle like ****.
working away until the weekend so I will be checking the VTA voltages then. Will have a look at the manual you posted above tonight.. Which section of the manual do I need to be looking at, had a little look a few days ago but didn\'t manage to find it, cheers again for the help.
ignore my simpleness, found the section I was looking for..... wish me luck...
Got home earlier than I thought so managed to adjust my VTA voltages. I adjusted the TPS once the engine was up to running temperature and with the engine off. I set VTA1 to 0.80V and the VTA2 increased to 1.69V and when I pressed the accelerator pedal fully down it gave the readings of VTA1 4.72V and VTA2 4.97V. She started well and idled perfectly, gave her a good blast for half an hour and she ran perfect. Got back home and restarted her a few times and she hasn\'t failed to start yet, Fantastic! So far I think that has sorted out the initial problem, I\'m over the bloody moon! Thanks to everyone who gave me advice especially Dr-Rotor, will let you know how she is going after I get some more use out of her.
Im very glad to hear it all works properly. Many happy miles of thrashing. Enjoy!
sounds hopeful, well done for adjusting the tps and good luck !!!
Awesomenesses.
Thanks god you didnt just leave it and become another \'bloody unreliably rotary!\' story
Hi Chaps sorry to liven this one back u but I have the same problem.. Hot start very dodgy. I have to give it some gas to get it to start.Only issue is I don\'t have a PFC to check the TPS voltage? (Well I do but it\'s not plugged in or mapped yet!) Can anyone suggest how I can do it without or if I can give it a tweak one way or tutther to see if it starts better or worse? I have a leaking LIM gasket so maybe that is not helping? I\'ll check the plugs too but I know they are NGK\'s!
thanks Lee
hi guys any body got a pic off the tps thanks