928 s troublesome refuses to start
05-09-2015, 05:37 PM
#1
Rennlist Member
Thread Starter
928 s troublesome refuses to start
Well the Saga continues.. got my LH computer and MAS back from rebuilder. installed all parts incl. new Temp 2 sensor. SAME dam thing engine will not start.. fuel pump only runs when jumped out relay. Now engine will start only with either tries to start with jumped out relay but will not stay running. Got it running on either but now the tach doe's not work before it did.. seems to be getting worse not better.. Fustrating..
05-10-2015, 09:26 AM
#3
^^^^ this...
When I introduced myself, I gave my date of birth, SS number, credit and debit card numbers...pins included and bank account information. Granted, I did all of that so I could blame our diminishing bank account and credit card balances on the rennlist members here...instead of my wife finding out it was the old 928 parked in the garage...and her beating my brains out with a pipe wrench...lol
But, seriously...some background on you and your car could be helpful. Knowing a persons mechanical abilities make giving advice easier.
As far as your issue with your car goes...a lot of folks here have had issues with their cars CPS (crank positioning sensor) or its connection and experenced similar problems.
Good luck, with your car.
Brian.
When I introduced myself, I gave my date of birth, SS number, credit and debit card numbers...pins included and bank account information. Granted, I did all of that so I could blame our diminishing bank account and credit card balances on the rennlist members here...instead of my wife finding out it was the old 928 parked in the garage...and her beating my brains out with a pipe wrench...lol
But, seriously...some background on you and your car could be helpful. Knowing a persons mechanical abilities make giving advice easier.
As far as your issue with your car goes...a lot of folks here have had issues with their cars CPS (crank positioning sensor) or its connection and experenced similar problems.
Good luck, with your car.
Brian.
05-10-2015, 11:36 AM
#4
Rennlist Member
Thread Starter
Sorry, My name is Mark Thornton 67 yrs old retired Auto restorer Classic British cars mostly Jaguar Mg Triumph ect. this is my first Porsche 1985 928 s 5 speed.. It has not ran in 8 yrs. cleaned out the gas tank, installed new sender new fuel pump and filter . cleaned all fuel lines. installed new crank pos sensor got it running with jumped out fuel relay. sent MAS and LH comp. to rebuilder , LH had bad fuel pump ground sector.. MAS needed t be calibrated and updated.. Installed new Temp 2 sender , installed MAS new gaskets new air filter, installed LH computer. Engine now will not start unless either is shot down intake. when it did run I noticed the tach. did not work fuel gauge and temp sender all inop.. Fuel pump runs when I jump out relay engine trys to start be will not catch.. Fustrated..
05-10-2015, 08:42 PM
#7
Nordschleife Master
Fuel pump not running without jumpering and no tach movement suggest that the crank sensor signal isn't reaching the LH. Bad sensor? Bad wiring? Bad LH? (yes, I read that the CPS is new and the LH is back from the rebuilder).
Duh-huh. If it's running on starting fluid, the CPS is working fine. I don't see that you've replaced the FP relay, you might try that. Also, if it's been sitting that long, a CE panel refresh is probably a good idea. There are a few writeups on this, it's not too difficult. I've used Sharkskin's:
http://members.rennlist.com/sharkski...04-Bzzzzzt.htm
And we generally refer to the Mass Air Flow Sensor as a "MAF" (a little bit picky, but it helps when you use the terminology we are used to).
Welcome. Keep posting details (about the car) and you will get help. It sounds like you know which end of the screwdriver to put on the screw (some people really don't).
And there's a little running gag that happens to new people -
Thread...
Duh-huh. If it's running on starting fluid, the CPS is working fine. I don't see that you've replaced the FP relay, you might try that. Also, if it's been sitting that long, a CE panel refresh is probably a good idea. There are a few writeups on this, it's not too difficult. I've used Sharkskin's:
http://members.rennlist.com/sharkski...04-Bzzzzzt.htm
And we generally refer to the Mass Air Flow Sensor as a "MAF" (a little bit picky, but it helps when you use the terminology we are used to).
Welcome. Keep posting details (about the car) and you will get help. It sounds like you know which end of the screwdriver to put on the screw (some people really don't).
And there's a little running gag that happens to new people -
Thread...
Last edited by Wisconsin Joe; 05-10-2015 at 10:31 PM.
Trending Topics
05-11-2015, 09:50 AM
#8
Rennlist Member
Thread Starter
928 Saga
Yes i have changed out the relay with a new one.. I got spark before I changed out the CPS i had only one spark then nothing., after I changed out that part it ran with a jumpered fuel pump relay but would not rev over 3k i sent out the Mass air flow sensor and the LH computer and it was confirmed I had indeed a bad LH comp. I changed it out with a known good one and at present Also changed out the Temp 2 sensor just for the hell of it. Now I am at my wits end with it.
05-11-2015, 05:15 PM
#10
Rennlist Member
also, you are less than a month and not many miles from on of the greatest 928 gatherings on the planet (search SITM). Go with another car and meet great people, many of whom will be glad to help. I grew up in Hickory, BTW, will be visiting my sis this summer so maybe can get in touch.
Last edited by M. Requin; 05-11-2015 at 05:57 PM.