weird no spark on stock FD

dregg100 · 11-21-2008, 01:58 PM

car started fine two weeks ago. went out last week to move it and nothing. engine was coming out for a rebuild(bad coolant seal) so i went through and cleaned all the grounds, cleaned the faces of the crank angle sensors etc.
engine is back in with same problem

i have fuel but no spark. fuses are good as are the relays. swapped out coils with known good ones. swapped out igniter, plug wires, and plugs. still nothing. any ideas?

***Herblenny*** · 11-21-2008, 02:08 PM

Did you replace the ECU or anything? Just curious.. I was helping with someone who did a auto to manual swap and it was something to do with ECU harness.. I can't remember exactly what it was though... its been 1+ year ago.

David Jerome · 11-21-2008, 02:56 PM

Do you have fuel pressure or have you verified the fuel injectors are actually firing?

Is the rpm needle bouncing slightly as you crank the car over?

David

dregg100 · 11-22-2008, 12:45 AM

ecu didnt change and this car was always manual. i havent "verified" that the injectors are working with a node or anything, but based on the fuel clouds coming out of the spark plug holes while cranking, its there. i pulled the egi fuse to see if the fuel stopped and it did then plugged it back in and it started again. fuel pressure is good.

i was thinking about the tach thing tonight, but have not looked. will do tomorrow.

also david, i got the als seals today!!

David Jerome · 11-22-2008, 11:06 AM

Quote:

Originally Posted by dregg100

ecu didnt change and this car was always manual. i havent "verified" that the injectors are working with a node or anything, but based on the fuel clouds coming out of the spark plug holes while cranking, its there. i pulled the egi fuse to see if the fuel stopped and it did then plugged it back in and it started again. fuel pressure is good.

i was thinking about the tach thing tonight, but have not looked. will do tomorrow.

also david, i got the als seals today!!

Glad you go the seals, let us know when you check the tach, however if fuel is coming out the spark plug holes then I am sure the tach will be bouncing.

dregg100 · 11-22-2008, 01:12 PM

no tach bouncing and i have no signal to the plugs that attach to the coils. they have the 12v constant, but no ground signal while cranking. guess i should check at the ecu.

dregg100 · 11-22-2008, 02:31 PM

did some more testing and it seems that the harness is the culprit. crank angle sensors test out good. but there is no continuity between the harness connector and the pin at the ecu for the sensor. also no resistance between the the pins on the harness at the ecu for the sensors. yay for a new harness

anybody got one for sale?

dregg100 · 11-25-2008, 02:01 PM

update

got the harness out today and found some interesting stuff. somewhere along the lines an owner of the car cut the CAS wires and respliced them. but when i say "respliced" i mean stripped the insulation off, twisted the bare wires together, and wrapped in electrical tape!!! i am flat amazed that the car ever ran. the crazy part is, when it was running, it ran fantastic! new harness going in tomorrow so we shall see.

***Herblenny*** · 11-25-2008, 03:35 PM

COOL!

Glad you found the problem!

I do have a good used harness.. but I guess its too late..

IR Performance · 11-25-2008, 08:29 PM

Those are shielded wires and should not be messed with unless you know what you are doing. Whoever messed with it shouldn't touch a car. If you can afford it the best option would be to go for a new harness.

dregg100 · 11-26-2008, 12:49 AM

i have a friend with quite a few harnesses laying around. and i got the best one(really nice actually). it will be going in tomorrow.

i knew they were shielded and there is a damn good reason for it. the shielding was gone from about 4 inches, and i am still laughing at the fact that the wires were twisted together!

dregg100 · 11-27-2008, 12:22 AM

new harness installed this morning and we have spark again!! now to just find time tomorrow to put the UIM back on and fire it up.

dregg100 · 11-28-2008, 11:32 PM

new rebuild started first try. it was fun smoking out the neighborhood on thanksgiving! now to finish the break in!

11-21-2008, 01:58 PM	#1
dregg100 Rotary Fanatic Join Date: Feb 2008 Posts: 432 Rep Power: 18	weird no spark on stock FD car started fine two weeks ago. went out last week to move it and nothing. engine was coming out for a rebuild(bad coolant seal) so i went through and cleaned all the grounds, cleaned the faces of the crank angle sensors etc. engine is back in with same problem i have fuel but no spark. fuses are good as are the relays. swapped out coils with known good ones. swapped out igniter, plug wires, and plugs. still nothing. any ideas? __________________ '93 SSM Touring-S475... '87 Tii-LS1/T56

11-21-2008, 02:08 PM	#2
*Herblenny* Founder/Administrator/Internet Pitbull :) Join Date: Jan 2008 Posts: 644 Rep Power: 10	Did you replace the ECU or anything? Just curious.. I was helping with someone who did a auto to manual swap and it was something to do with ECU harness.. I can't remember exactly what it was though... its been 1+ year ago. __________________ DGRR 2013 - Year of 13B www.DealsGapRotaryRally.com http://www.facebook.com/Herblenny

11-21-2008, 02:56 PM	#3
David Jerome RCC Contributor Join Date: Jan 2008 Posts: 713 Rep Power: 18	Do you have fuel pressure or have you verified the fuel injectors are actually firing? Is the rpm needle bouncing slightly as you crank the car over? David __________________ David Jerome Broker for Speed For Sale LLC (David@SpeedForSale.com) (Pre-owned RX7/sports car sales & new parts sales/installs/tuning) PM me about low priced, high quality port work

11-22-2008, 12:45 AM	#4
dregg100 Rotary Fanatic Join Date: Feb 2008 Posts: 432 Rep Power: 18	ecu didnt change and this car was always manual. i havent "verified" that the injectors are working with a node or anything, but based on the fuel clouds coming out of the spark plug holes while cranking, its there. i pulled the egi fuse to see if the fuel stopped and it did then plugged it back in and it started again. fuel pressure is good. i was thinking about the tach thing tonight, but have not looked. will do tomorrow. also david, i got the als seals today!! __________________ '93 SSM Touring-S475... '87 Tii-LS1/T56 Last edited by dregg100; 11-22-2008 at 12:49 AM.

11-22-2008, 01:12 PM	#6
dregg100 Rotary Fanatic Join Date: Feb 2008 Posts: 432 Rep Power: 18	no tach bouncing and i have no signal to the plugs that attach to the coils. they have the 12v constant, but no ground signal while cranking. guess i should check at the ecu. __________________ '93 SSM Touring-S475... '87 Tii-LS1/T56

11-22-2008, 02:31 PM	#7
dregg100 Rotary Fanatic Join Date: Feb 2008 Posts: 432 Rep Power: 18	did some more testing and it seems that the harness is the culprit. crank angle sensors test out good. but there is no continuity between the harness connector and the pin at the ecu for the sensor. also no resistance between the the pins on the harness at the ecu for the sensors. yay for a new harness anybody got one for sale? __________________ '93 SSM Touring-S475... '87 Tii-LS1/T56 Last edited by dregg100; 11-22-2008 at 03:21 PM.

11-25-2008, 02:01 PM	#8
dregg100 Rotary Fanatic Join Date: Feb 2008 Posts: 432 Rep Power: 18	update got the harness out today and found some interesting stuff. somewhere along the lines an owner of the car cut the CAS wires and respliced them. but when i say "respliced" i mean stripped the insulation off, twisted the bare wires together, and wrapped in electrical tape!!! i am flat amazed that the car ever ran. the crazy part is, when it was running, it ran fantastic! new harness going in tomorrow so we shall see. __________________ '93 SSM Touring-S475... '87 Tii-LS1/T56

11-25-2008, 03:35 PM	#9
*Herblenny* Founder/Administrator/Internet Pitbull :) Join Date: Jan 2008 Posts: 644 Rep Power: 10	COOL! Glad you found the problem! I do have a good used harness.. but I guess its too late.. __________________ DGRR 2013 - Year of 13B www.DealsGapRotaryRally.com http://www.facebook.com/Herblenny

11-25-2008, 08:29 PM	#10
IR Performance Rotary Fanatic Join Date: Feb 2008 Location: Metuchen, NJ Posts: 249 Rep Power: 18	Those are shielded wires and should not be messed with unless you know what you are doing. Whoever messed with it shouldn't touch a car. If you can afford it the best option would be to go for a new harness. __________________ Providing rotary engine rebuilds, porting, turbo installs, parts installations, full maintenance, etc. We work on all cars. www.irperformance.com www.myspace.com/rotaryexperimentseven irperformance@live.com 732-662-1794

11-26-2008, 12:49 AM	#11
dregg100 Rotary Fanatic Join Date: Feb 2008 Posts: 432 Rep Power: 18	i have a friend with quite a few harnesses laying around. and i got the best one(really nice actually). it will be going in tomorrow. i knew they were shielded and there is a damn good reason for it. the shielding was gone from about 4 inches, and i am still laughing at the fact that the wires were twisted together! __________________ '93 SSM Touring-S475... '87 Tii-LS1/T56

11-27-2008, 12:22 AM	#12
dregg100 Rotary Fanatic Join Date: Feb 2008 Posts: 432 Rep Power: 18	new harness installed this morning and we have spark again!! now to just find time tomorrow to put the UIM back on and fire it up. __________________ '93 SSM Touring-S475... '87 Tii-LS1/T56

11-28-2008, 11:32 PM	#13
dregg100 Rotary Fanatic Join Date: Feb 2008 Posts: 432 Rep Power: 18	new rebuild started first try. it was fun smoking out the neighborhood on thanksgiving! now to finish the break in! __________________ '93 SSM Touring-S475... '87 Tii-LS1/T56