Pennock's Fiero Forum
  Technical Discussion & Questions
  DOHC Starting Issues, BIG Puzzler! (Page 2)

Post New Topic  Post A Reply
Email This Page to Someone! | Printable Version

This topic is 2 pages long:  1   2 
Previous Page | Next Page
next newest topic | next oldest topic
DOHC Starting Issues, BIG Puzzler! by Squeaky
Started on: 06-29-2013 04:17 PM
Replies: 48 (990 views)
Last post by: Erik on 08-19-2013 10:49 PM
tesmith66
Member
Posts: 7355
From: Jerseyville, IL
Registered: Sep 2001


Feedback score: (3)
Leave feedback





Total ratings: 135
Rate this member

Report this Post08-16-2013 06:40 AM Click Here to See the Profile for tesmith66Send a Private Message to tesmith66Edit/Delete MessageReply w/QuoteDirect Link to This Post
Remove the upper intake manifold and make sure none of the injector wires got pinched when you replaced the fuel rail.

------------------
1986 SE Aero coupe.

3.4 DOHC swap is complete and running, now just have to finish the rest of the car...

[This message has been edited by tesmith66 (edited 08-16-2013).]

IP: Logged
Squeaky
Member
Posts: 162
From: Edmonton, AB
Registered: Sep 2009


Feedback score: (3)
Leave feedback

Rate this member

Report this Post08-16-2013 11:09 AM Click Here to See the Profile for SqueakySend a Private Message to SqueakyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Erik:

The fuse that's blowing most likely goes to your DIS. Disconnect the C203 connector . Take the multimeter and test for continuity at pin J on the C203 connector with the other probe at pin B ( pink/ black wire) of your 2 pin connector that plugs into the DIS/ICM. Make sure it's unplugged from the DIS. If that checks out then we know that the TBI INJ 1 powers the DIS. Then from that point touch a probe on pin J of the C203 and leave the two pin connector unplugged from the DIS and take the other probe and touch it to ground and check for continuity. If it does check out then it shorting somewhere along the wire. If not then somethings up with your ICM. After the fuse blows you could turn the ignition key switch to the on position and check to see if the DIS pin B is getting 12 V as well. If it is then it's running off another circuit. Several of the wiring harnesses that I have built power the DIS off of the C500 @ E3 pin. This test is to confirm that your DIS is running off of the TBI INJ 1 circuit that's blowing the fuse. Once we determine what TBI INJ 1 powers then we can move from there.


Electronics are not my forte (as you all may have guessed) but I get what your saying. Thanks for that Erik!! I will start tackling that this weekend, it ran beautifully before so there's no reason why it shouldn't again. I will follow your directions and continue to go from there thanks again!


IP: Logged
Squeaky
Member
Posts: 162
From: Edmonton, AB
Registered: Sep 2009


Feedback score: (3)
Leave feedback

Rate this member

Report this Post08-17-2013 03:17 PM Click Here to See the Profile for SqueakySend a Private Message to SqueakyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Erik:

The fuse that's blowing most likely goes to your DIS. Disconnect the C203 connector . Take the multimeter and test for continuity at pin J on the C203 connector with the other probe at pin B ( pink/ black wire) of your 2 pin connector that plugs into the DIS/ICM. Make sure it's unplugged from the DIS. If that checks out then we know that the TBI INJ 1 powers the DIS. Then from that point touch a probe on pin J of the C203 and leave the two pin connector unplugged from the DIS and take the other probe and touch it to ground and check for continuity. If it does check out then it shorting somewhere along the wire. If not then somethings up with your ICM. After the fuse blows you could turn the ignition key switch to the on position and check to see if the DIS pin B is getting 12 V as well. If it is then it's running off another circuit. Several of the wiring harnesses that I have built power the DIS off of the C500 @ E3 pin. This test is to confirm that your DIS is running off of the TBI INJ 1 circuit that's blowing the fuse. Once we determine what TBI INJ 1 powers then we can move from there.


So I took my multi-meter and tested for continuity at pin J on my C203 connector, with my other probe at the at pin b (pink/black) on my 2 pin DIS/ICM connector. Although it didn't check out and there was no continuity.

I then did the same except this time I put the probe on the ground of my 2 pin DIS/ICM connector and this time it checked out and there was continuity. Based on that it must be shorting somewhere along the wire, correct?

After my fuse blew I turned the key to the 'on' position and tested for 12V at pin B on my DIS/ICM connector, although I wasn't getting any voltage. Meaning that we've just confirmed that my DIS is running off the TBI INJ 1 circut.

[This message has been edited by Squeaky (edited 08-17-2013).]

IP: Logged
Squeaky
Member
Posts: 162
From: Edmonton, AB
Registered: Sep 2009


Feedback score: (3)
Leave feedback

Rate this member

Report this Post08-17-2013 09:27 PM Click Here to See the Profile for SqueakySend a Private Message to SqueakyEdit/Delete MessageReply w/QuoteDirect Link to This Post

Squeaky

162 posts
Member since Sep 2009
 
quote
Originally posted by Squeaky:


So I took my multi-meter and tested for continuity at pin J on my C203 connector, with my other probe at the at pin b (pink/black) on my 2 pin DIS/ICM connector. Although it didn't check out and there was no continuity.

I then did the same except this time I put the probe on the ground of my 2 pin DIS/ICM connector and this time it checked out and there was continuity. Based on that it must be shorting somewhere along the wire, correct?

After my fuse blew I turned the key to the 'on' position and tested for 12V at pin B on my DIS/ICM connector, although I wasn't getting any voltage. Meaning that we've just confirmed that my DIS is running off the TBI INJ 1 circut.



Based on this I figured the next logical step was to start chasing the power wire (pink/black) from pin B on my DIS/ICM connector in hopes of finding where it might be shorting. I chased it all the way down to where the pink/black power wire is then soldered and heat-shinked to a pink/white wire, from there it travels through my firewall. I still haven't seen any physical signs of where it might be shorting.

Once past my firewall and in my interior the pink/white wire has a yellow wire spliced into it that goes back out the firewall and to the engine, what is it for and where does it go?

That same pink/white wire after its through my firewall goes to pin J on my C203 connector which then goes to the TBI INJ 1 slot on my fusebox.

Because I can't see any physical damage on pink/white wire I'm thinking the next step might be to then follow that yellow wire, thoughts?

IP: Logged
Erik
Member
Posts: 5625
From: Des Moines, Iowa
Registered: Jul 2002


Feedback score: (3)
Leave feedback





Total ratings: 168
Rate this member

Report this Post08-18-2013 01:50 AM Click Here to See the Profile for ErikSend a Private Message to ErikEdit/Delete MessageReply w/QuoteDirect Link to This Post
Does the fuse blow if you have your DIS power connector unplugged from the ICM and of course the C203 plugged in? With the C 203 unplugged and one probe @ pin J touch the other probe on the engine block and check for continuity. If that checks then there is a short. Also check for continuity between the engine block and pin B of the DIS/ICM 2 pin connector. The yellow wire I am confused about ..it's actually spliced into the pink /white wire that goes to pin J? There is a yellow wire that comes from your VSS that goes to pin G. And there is another wire that is yellow that comes from your ECM C8 pin That is spliced into your purple wire at pin R of your C2 03.
IP: Logged
Squeaky
Member
Posts: 162
From: Edmonton, AB
Registered: Sep 2009


Feedback score: (3)
Leave feedback

Rate this member

Report this Post08-18-2013 06:29 PM Click Here to See the Profile for SqueakySend a Private Message to SqueakyEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yes, with my C203 connector plugged in the fuse blows with my DIS connector unplugged from my icm.

I checked for continuity with my C203 unplugged with pin j probed and my other probe on the engine block, still no continuity.

Yes the yellow wire is spliced into the pink/white wire that comes from my J pin on the C203

After reading back in my thread I noticed that I realized the 5amp TBI INJ 1 fuse was blowing after I spliced in a new connector... I'm wondering if perhaps I accidently spliced it in incorrectly by mixing up the wires on my C203 at pin R and pin J... Could symptoms like the ones I've been experiencing be a result of that?
IP: Logged
Erik
Member
Posts: 5625
From: Des Moines, Iowa
Registered: Jul 2002


Feedback score: (3)
Leave feedback





Total ratings: 168
Rate this member

Report this Post08-19-2013 01:02 PM Click Here to See the Profile for ErikSend a Private Message to ErikEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Squeaky:

Yes, with my C203 connector plugged in the fuse blows with my DIS connector unplugged from my icm.

I checked for continuity with my C203 unplugged with pin j probed and my other probe on the engine block, still no continuity.

Yes the yellow wire is spliced into the pink/white wire that comes from my J pin on the C203

After reading back in my thread I noticed that I realized the 5amp TBI INJ 1 fuse was blowing after I spliced in a new connector... I'm wondering if perhaps I accidently spliced it in incorrectly by mixing up the wires on my C203 at pin R and pin J... Could symptoms like the ones I've been experiencing be a result of that?


Yes that could cause it. There should not be a yellow wire sharing pin J with the pink/white wire. I would check to see if the yellow wire is either coming from the VSS connector or C8 pin on the ECM plug.
IP: Logged
Squeaky
Member
Posts: 162
From: Edmonton, AB
Registered: Sep 2009


Feedback score: (3)
Leave feedback

Rate this member

Report this Post08-19-2013 09:24 PM Click Here to See the Profile for SqueakySend a Private Message to SqueakyEdit/Delete MessageReply w/QuoteDirect Link to This Post
She fired!!! I switched pin J with pin R on my C203, it my infinite wisdom I must've spliced the C203 connector in inncorrectly... Surely one of those mistakes I'll never make again after all this.

Thanks Erik for building my harness, sorry for effing it up haha. Your expertise has been incredibly helpful, thanks to all other's for your helpful advice and suggestions. Now if I could only get the pennock's image poster working on my computer, would love to get up some pics!
IP: Logged
Erik
Member
Posts: 5625
From: Des Moines, Iowa
Registered: Jul 2002


Feedback score: (3)
Leave feedback





Total ratings: 168
Rate this member

Report this Post08-19-2013 10:49 PM Click Here to See the Profile for ErikSend a Private Message to ErikEdit/Delete MessageReply w/QuoteDirect Link to This Post
Sweet! Glad to hear you got it solved.
IP: Logged
Previous Page | Next Page

This topic is 2 pages long:  1   2 
next newest topic | next oldest topic

All times are ET (US)

Post New Topic  Post A Reply
Hop to:

Contact Us | Back To Main Page

Advertizing on PFF | Fiero Parts Vendors
PFF Merchandise | Fiero Gallery | Ogre's Cave
Real-Time Chat | Fiero Related Auctions on eBay



Copyright (c) 1999, C. Pennock