C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Help - 1990 No Start!

Thread Tools
 
Search this Thread
 
Old 06-10-2024, 04:17 PM
  #1  
TorchLT4
Instructor
Thread Starter
 
TorchLT4's Avatar
 
Member Since: Sep 2020
Location: Sullivan, MO
Posts: 114
Received 45 Likes on 32 Posts
Default Help - 1990 No Start!

Alright fellas, I am at my wits end and could use some assistance. Most of my previous builds were carbureted, so if you had fuel/air/spark and your timing was close the engine would run. Not so with this thing. I have used my service manual to troubleshoot and searched this forum, but I am still stuck.

1990 L98 ZF6
Edelbrock Pro FloXT intake and TB
Bosch # 30lb injectors
Davis Unified HEI distributor with seperate coil
AEM Fuel Pump and Adj FPR
Comp 276 Cam with 1.6 roller rockers
AFR Enforcer Heads
Ran Great before the distributor moved and the timing was off.

It cranks but does not try to hit.
Battery charged.
Noid Light says injectors are getting signal.
Spark plug Test light shows spark, and was able to get a plug to arc while pulled from the head.
Fuel Pressure is good @ 45lbs.
Does not hit on starting fluid.
185-190 lbs compression
Replaced: plugs, ECM, TPS sensor
5v at TPS
Made sure timing was good.
NO codes are thrown
I really don't want to have to pony up for a Holley system as this thing was rock solid reliable before.

Any thoughts or suggestions for what to try. I have pretty well exhausted my service manuals with no luck. Help Please!

Last edited by TorchLT4; 06-10-2024 at 04:47 PM. Reason: Added info
Old 06-10-2024, 04:52 PM
  #2  
jv9999
Melting Slicks
 
jv9999's Avatar
 
Member Since: Jan 2014
Location: Lunenburg MA
Posts: 2,043
Received 329 Likes on 281 Posts

Default

If you pull a plug after trying to start it, are they wet? Have you tried a little ether or even brake cleaner in the throttle body? My first thought is you're not getting fuel (despite the noid light). Did you remove the distributor? I guess the timing could be so far off that it's spraying fuel into cylinders with a valve open. You can try a timing light while it's cranking to see if it's close.
Old 06-10-2024, 04:57 PM
  #3  
TorchLT4
Instructor
Thread Starter
 
TorchLT4's Avatar
 
Member Since: Sep 2020
Location: Sullivan, MO
Posts: 114
Received 45 Likes on 32 Posts
Default

Thanks for the reply.

The distribtor had moved due to a cheap chrome hold down, so I just replaced it with a MSD unit and set the base timing at 6 degrees.

Would not hit on Blake Cleaner/Starting Fluid. Plug wet with fuel.
Old 06-10-2024, 05:02 PM
  #4  
jv9999
Melting Slicks
 
jv9999's Avatar
 
Member Since: Jan 2014
Location: Lunenburg MA
Posts: 2,043
Received 329 Likes on 281 Posts

Default

Something can't be what it appears to be. If you have compression, fuel and spark at the right time, it's going to fire.
Old 06-10-2024, 05:04 PM
  #5  
TorchLT4
Instructor
Thread Starter
 
TorchLT4's Avatar
 
Member Since: Sep 2020
Location: Sullivan, MO
Posts: 114
Received 45 Likes on 32 Posts
Default

Originally Posted by jv9999
Something can't be what it appears to be. If you have compression, fuel and spark at the right time, it's going to fire.
My thoughts exactly, hence my frustration!
Old 06-10-2024, 05:11 PM
  #6  
jv9999
Melting Slicks
 
jv9999's Avatar
 
Member Since: Jan 2014
Location: Lunenburg MA
Posts: 2,043
Received 329 Likes on 281 Posts

Default

Since the timing is the last thing you touched before it stopped running, I would look at that again. Make sure you're not 180 degrees out. I've done it more than once.

Get notified of new replies

To Help - 1990 No Start!




Quick Reply: Help - 1990 No Start!



All times are GMT -4. The time now is 05:44 PM.