Any experiences with code 42? 87 Iroc
#1
Junior Member
Thread Starter
Join Date: Apr 2009
Location: Montreal, Quebec, Canada
Posts: 47
Likes: 0
Received 0 Likes
on
0 Posts
Car: 87 Iroc-z
Engine: 350/340 hp, 400lb-ft GM crate
Transmission: custom built 700r4
Axle/Gears: 3.73
Any experiences with code 42? 87 Iroc
Ok guys, please help me out! It suddenly died, won't start, ran great juste before. I get a 42 code. I unplugged my msd to try and don't have spark. What could it be!?
#3
Junior Member
Thread Starter
Join Date: Apr 2009
Location: Montreal, Quebec, Canada
Posts: 47
Likes: 0
Received 0 Likes
on
0 Posts
Car: 87 Iroc-z
Engine: 350/340 hp, 400lb-ft GM crate
Transmission: custom built 700r4
Axle/Gears: 3.73
Re: Any experiences with code 42? 87 Iroc
By ignition module you mean? The coil is rather new... You know tests i can do to verify components? I replaced thethe cap and rotor a week before. Had to pull out the distributer to repair a broken screw of the old cap. Retimed it afterwards and nothing moved it ran perfectly just before it died......
Last edited by therain2008; 06-20-2015 at 08:42 AM.
#4
Supreme Member
iTrader: (14)
Re: Any experiences with code 42? 87 Iroc
Like Twin_Turbo said, it's likely a bad ign module under the dist cap. http://www.chevythunder.com/est_code_42.htm
#5
Junior Member
Join Date: Jun 2014
Location: Sacramento, CA
Posts: 17
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1990 Iroc-z
Engine: LS3/LSA blower
Transmission: T56
Axle/Gears: 3.27
Re: Any experiences with code 42? 87 Iroc
I have the same code also I've been trying to figure out what the problem is, I've already replaced my distributor, computer, prom, so I think that the est or bypass is frayed somewhere, is it possible to just place a new white and tan/black wire from the distributor to the ecm rather than taking apart the wire harness
#6
Junior Member
Thread Starter
Join Date: Apr 2009
Location: Montreal, Quebec, Canada
Posts: 47
Likes: 0
Received 0 Likes
on
0 Posts
Car: 87 Iroc-z
Engine: 350/340 hp, 400lb-ft GM crate
Transmission: custom built 700r4
Axle/Gears: 3.73
Re: Any experiences with code 42? 87 Iroc
Like Twin_Turbo said, it's likely a bad ign module under the dist cap. http://www.chevythunder.com/est_code_42.htm
#7
Junior Member
Thread Starter
Join Date: Apr 2009
Location: Montreal, Quebec, Canada
Posts: 47
Likes: 0
Received 0 Likes
on
0 Posts
Car: 87 Iroc-z
Engine: 350/340 hp, 400lb-ft GM crate
Transmission: custom built 700r4
Axle/Gears: 3.73
Re: Any experiences with code 42? 87 Iroc
Well... Still no fuego after replacing the ignition module, i have spark from the coil up to the tip of the wire of the center of the cap but nothing at the end of the wires to the plugs... Any ideas?
Trending Topics
#8
Member
iTrader: (5)
Join Date: Aug 2006
Location: Stafford, Connecticut
Posts: 311
Likes: 0
Received 1 Like
on
1 Post
Car: 87 Iroc
Engine: modified 350
Transmission: high performance built 700R4
Axle/Gears: Strange S60 3:73
Re: Any experiences with code 42? 87 Iroc
If you have an MSD control box it is probably the problem.Go back to the factory ignition system and I bet it will start right up.I bought both The MSD and Crane spark boxes and both went out within 6 months.I put the factory stuff back in problem solved.
#9
Supreme Member
Re: Any experiences with code 42? 87 Iroc
Check the ground wire on the ESC box by the firewall. Check the whole connector for that matter and make sure none of the wires are corroded or pulled back.
#10
Junior Member
Thread Starter
Join Date: Apr 2009
Location: Montreal, Quebec, Canada
Posts: 47
Likes: 0
Received 0 Likes
on
0 Posts
Car: 87 Iroc-z
Engine: 350/340 hp, 400lb-ft GM crate
Transmission: custom built 700r4
Axle/Gears: 3.73
Re: Any experiences with code 42? 87 Iroc
I disconnected the msd and same thing
#11
Junior Member
Thread Starter
Join Date: Apr 2009
Location: Montreal, Quebec, Canada
Posts: 47
Likes: 0
Received 0 Likes
on
0 Posts
Car: 87 Iroc-z
Engine: 350/340 hp, 400lb-ft GM crate
Transmission: custom built 700r4
Axle/Gears: 3.73
#12
Senior Member
iTrader: (1)
Join Date: Dec 2012
Location: Western NY
Posts: 629
Likes: 0
Received 2 Likes
on
2 Posts
Car: 88 convertible
Engine: 5.7L
Transmission: 4+3 maual
Axle/Gears: 3.07
Re: Any experiences with code 42? 87 Iroc
If you have spark at the coil wire going to the distributor then the only parts in between the coil wire and spark plugs is the rotor and the cap itself and of course the spark plug wires. Check your rotor for a broken tip and check the cap for broken terminals inside the cap. HTH!
#13
Junior Member
Thread Starter
Join Date: Apr 2009
Location: Montreal, Quebec, Canada
Posts: 47
Likes: 0
Received 0 Likes
on
0 Posts
Car: 87 Iroc-z
Engine: 350/340 hp, 400lb-ft GM crate
Transmission: custom built 700r4
Axle/Gears: 3.73
Re: Any experiences with code 42? 87 Iroc
If you have spark at the coil wire going to the distributor then the only parts in between the coil wire and spark plugs is the rotor and the cap itself and of course the spark plug wires. Check your rotor for a broken tip and check the cap for broken terminals inside the cap. HTH!
#14
Senior Member
iTrader: (1)
Join Date: Dec 2012
Location: Western NY
Posts: 629
Likes: 0
Received 2 Likes
on
2 Posts
Car: 88 convertible
Engine: 5.7L
Transmission: 4+3 maual
Axle/Gears: 3.07
Re: Any experiences with code 42? 87 Iroc
No, the ignition system and ecm control the primary side of the coil. If you have spark at the coil going to the distributor cap then the primary circuit is fine. The secondary side of the coil produces the spark that fires the plugs. If you have spark coming from the coil then the problem is with the cap, rotor or wires as stated earlier.
#15
Junior Member
Thread Starter
Join Date: Apr 2009
Location: Montreal, Quebec, Canada
Posts: 47
Likes: 0
Received 0 Likes
on
0 Posts
Car: 87 Iroc-z
Engine: 350/340 hp, 400lb-ft GM crate
Transmission: custom built 700r4
Axle/Gears: 3.73
Re: Any experiences with code 42? 87 Iroc
No, the ignition system and ecm control the primary side of the coil. If you have spark at the coil going to the distributor cap then the primary circuit is fine. The secondary side of the coil produces the spark that fires the plugs. If you have spark coming from the coil then the problem is with the cap, rotor or wires as stated earlier.
Thread
Thread Starter
Forum
Replies
Last Post
mustangman65_79
Body
3
08-11-2015 03:17 PM