Pennock's Fiero Forum
  Technical Discussion & Questions
  Not getting spark...suspected ICM and Oil Pressure switch as culprits, HELP!

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


next newest topic | next oldest topic
Not getting spark...suspected ICM and Oil Pressure switch as culprits, HELP! by zefferk
Started on: 01-02-2015 12:25 PM
Replies: 4 (111 views)
Last post by: zefferk on 01-02-2015 01:03 PM
zefferk
Member
Posts: 1019
From: Gold Canyon, Arizona
Registered: Feb 2010


Feedback score:    (69)
Leave feedback

Rate this member

Report this Post01-02-2015 12:25 PM Click Here to See the Profile for zefferkSend a Private Message to zefferkEdit/Delete MessageReply w/QuoteDirect Link to This Post
So i have spent the greater part of the last year completely redoing my 88 formula. I have finally got everything reassembled, but cannot get spark to the plugs. The car ran fine before I took it apart. I replaced most of the sensors, but only cut into the wiring harness to replace the high pressure switch on the A/C compressor which now has a two wire connector. The compressor is new and so is the switch. When I turn the key to run the fan and blower come on. When I disconnect the high pressure switch they turn off. According to the manual, this means I have a bad sensor. Thought this might have some bearing on the no spark issue some way, but I can't figure how.

I have tried to disconnect the oil pressure switch to see if that might be the problem, and when I did, I would get electricity to the connector to the coil. I wasn't getting any oil pressure reading prior to this either. The gauge would stay flat when I would crank the motor. When I disconnected the oil pressure switch, it would spike out, but I would get juice to the coil. I replaced the oil pressure switch, but still have no pressure reading at the gauge and the car still won't start. I unhooked my new coil and used the old one that worked fine before dis-assembly, and still no spark.

I then checked my ICM. Took the new one off and installed the prior older one that worked before the dis-assembly and nothing... Had the new ICM checked, and it tests fine...

What in the world could be wrong? I am not the best with electrical stuff, so if you have any suggestions, could you be so kind as to explain what I need to check and how like you were telling a novice please? I'd really appreciate any help anyone might be able to provide. I want my car back on the road and have spent a ton of money redoing the entire car....suspension, cooling, A/C, new heads, new exhaust, new front battery...essentially the car is mechanically new!

------------------
My Fiero...

88 Yellow formula CJB #182 of 1252

IP: Logged
PFF
System Bot
Gall757
Member
Posts: 10661
From: Holland, MI
Registered: Jun 2010


Feedback score: N/A
Leave feedback





Total ratings: 88
Rate this member

Report this Post01-02-2015 12:35 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
Confirm you have primary ignition by cranking the starter and watching the tach. It should go up to 300 rpm or so. If it does not go up, there is a problem with the ICM, pickup coil, distributor magnet, ignition coil, or the wiring and connectors for those items. If the tach moves, use starting fluid to confirm your fuel delivery system. If the car does not run on starter fluid, The high voltage (secondary) part of the ignition system is at fault.....distributor cap, wires and plugs...or the high voltage section in the ignition coil.(it has both low and high voltage in it).

edit: oil pressure switch has to do with the fuel pump..not ignition. Air Conditioner won't influence the ignition system either.

[This message has been edited by Gall757 (edited 01-02-2015).]

IP: Logged
zefferk
Member
Posts: 1019
From: Gold Canyon, Arizona
Registered: Feb 2010


Feedback score:    (69)
Leave feedback

Rate this member

Report this Post01-02-2015 12:44 PM Click Here to See the Profile for zefferkSend a Private Message to zefferkEdit/Delete MessageReply w/QuoteDirect Link to This Post
I know I am getting fuel as the new pump primes and you can smell the gas. Sounds like I am going to have to check more components. I need to see if the tach moves or not...I believe it does, but let me check... Tach moves slightly, but in reverse...
IP: Logged
Gall757
Member
Posts: 10661
From: Holland, MI
Registered: Jun 2010


Feedback score: N/A
Leave feedback





Total ratings: 88
Rate this member

Report this Post01-02-2015 12:48 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
Have you done a pickup coil test? You may want to test your ignition coil too....

IP: Logged
zefferk
Member
Posts: 1019
From: Gold Canyon, Arizona
Registered: Feb 2010


Feedback score:    (69)
Leave feedback

Rate this member

Report this Post01-02-2015 01:03 PM Click Here to See the Profile for zefferkSend a Private Message to zefferkEdit/Delete MessageReply w/QuoteDirect Link to This Post
I will try this next. Thanks. I'll let you know what I find.
IP: Logged

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