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tbi issues....1990 5.7

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Old 10-28-2013, 10:36 AM
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Default tbi issues....1990 5.7

I am having issues with my tbi.....I have spark,new icm,ecm,esc mod,throttle positioning sensor,fuel pump,in line filter,but I am not getting fuel to injectors....took injectors out and tested in another chevy truck they are fine....put noid light on them an no pulse.....help me....ps the truck will start if i pour gas down throttle body.....what am i missing???
 
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Old 10-29-2013, 11:56 AM
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So it's your fuel delivery system.

When you turn the key from off to the first position do you hear the fuel pump kick on? It should whir/buzz for 3-4 seconds.

There is a fuel pump relay on the firewall. There are also two fuses for the ECM/Fuel pump on the fuse block.
 
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Old 10-29-2013, 12:26 PM
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Fuel pump an relay are brand new....checked fuses also....theyre good....distributor ???
 
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Old 10-29-2013, 04:03 PM
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aiight. as far as im aware of the pick up coil in the distributor helps with injectors. try it. i think they are like 10 bucks.
 
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Old 10-30-2013, 10:02 AM
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im going to try the dist today...I hope it works cuz im already about 450.00 into this, and runnin out of funds fast
 
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Old 11-11-2013, 06:48 PM
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Default Using stock TBI base vs. bored unite

I tried a bored TBI unit on my K5 with 355 engine. I have a costume chip burned for my engine combination and the chip came with a high volume pump and high pressure spring for the pressure regulator. The engine is healthy with Dart 180 SHP heads, mild elgin cam, 9.8:1 compression.

The bored unit is very hard to seal and I ended up using JB weld to seal around the bores. When they bore the unit out the sealing area is about 1/16" thick, no good. I epoxied the unit to my adapter plate to make a good seal.

Idle is bad "loopy", but when I get on it engine screams.

I went back to my stock base TBI with injector pods and aftermarket spring/pressure regulator.

Idle is far better, and all around driving is better.

Unless you are beating the hell out of your engine or have a wild setup, stay with a stock TBI with better injectors and/or high pressure spring.

Good Wheeling.
 
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Old 11-11-2013, 06:51 PM
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Originally Posted by tattime
I am having issues with my tbi.....I have spark,new icm,ecm,esc mod,throttle positioning sensor,fuel pump,in line filter,but I am not getting fuel to injectors....took injectors out and tested in another chevy truck they are fine....put noid light on them an no pulse.....help me....ps the truck will start if i pour gas down throttle body.....what am i missing???
Check your pressure regulator. If the diaphragm is ripped or the spring is broke you will not get fuel. Check for debris in your fuel line at the TBI supply/return lines.
 
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Old 11-12-2013, 08:01 AM
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Problem fixed........it was the distributor ....apperantly this yr has cam sensor an crank sensor located inside of it
 
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Old 11-13-2013, 06:29 AM
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Good for you. I have had distributors go bad but usually no spark.
 
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Old 11-13-2013, 05:13 PM
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That is false, there is no cam or crank sensor in the distributor. Only sensor in the distributor is the ICM module.
 


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