Looking for TBI Expert Input

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Kilian

Full Access Member
Joined
Mar 25, 2018
Posts
221
Reaction score
39
Location
Wisconsin
First Name
K
Truck Year
1983
Truck Model
C2500 on its way to a K2500
Engine Size
350
Got an 87 350 TBI that I want to get running to use around the farm while working on my 83 project. I know little about TBI systems, so looking for some help with the current situation:

- Engine starts but idles rough.
- Runs better at faster speeds
- No check engine light
- New spark plugs (PO sent them along so I installed them)
- Both injectors seem to be spraying gas, engine smooths out a little when disconnecting one side or another.

Have a friend that has a scanner for seeing if there are any codes, not sure if all would trigger the check engine light.

Thoughts? I know it's not a lot of info but looking for some basic TBI things to look into. Thanks.
 

1985c20

Full Access Member
Joined
Jan 21, 2019
Posts
143
Reaction score
187
Location
Torrington, CT
First Name
Chuck
Truck Year
1985
Truck Model
C20
Engine Size
350
See if your buddy’s scanner can pull live data and check what the reported coolant temp is. My first guess would be your coolant temp sensor is bad showing a really cold value so your computer is dumping fuel to compensate. That’s why it runs a little better when you disconnect one fuel injector. TBI are pretty simple, it’s usually the coolant temp sensor, fuel pressure, or ignition when they stop running right.
 

gmbellew

Full Access Member
Joined
May 27, 2018
Posts
1,239
Reaction score
1,327
Location
Kansas city
First Name
glen
Truck Year
1990
Truck Model
suburban 1500
Engine Size
350
check the drivability and emissions manual in the reference library. it has a while section on things like this. I also like aldldroid and a Bluetooth OBD1 reader to see live data and help diagnose of your friends scanner can not see live data.
 

Latest posts

Forum statistics

Threads
44,416
Posts
957,124
Members
36,753
Latest member
TheRigLivesOn
Top