1984 K10 LS Swap - Lots of Little Problems

[Bextreme04]

I gave the wiring a quick check and the power and ground are going to the battery like required. I do not fully understand it, but the Terminator computer likes clean power and the battery is basically a big buffer/filter that provides the cleanest power. The connections from the Terminator to the sensors etc. is all with preterminated connectors so they should be in the right place. I checked the temp and pressure sensors that I could see and they were correct.

I have been trying to figure out what the effect of a dead cylinder would be on an overall rich condition and I'm really stuck. IMHO, a cylinder not getting any fuel should not have any effect and might make the engine seem lean because there is one cylinder of air being pumped through. [Hmmm --> maybe the Terminator is making everything richer to compensate?] 3 out of 8 cylinders have compression test results of about 180 psi. I'll do the remaining 5 cylinders soon. It might bite me in the @ss, but I will assume good enough compression overall for now. One thing I noticed was that the temperature of the exhaust pipes on the right side were about 100F cooler than the left side. The right exhaust smokes significantly more than the left side as well.

This leads me to believe that I might have leaky injectors. This engine sat for about two years while I gathered parts and tried to find time to start the swap. Maybe the injectors are gummed up. Since the swap, there is probably less than two hours of run time on the engine.

My next step is to pull, inspect and clean the injectors. I have some tools on the way to help with this. Depending on the results I will either repair or replace suspect injectors. BTW, South Bay Injectors is just a town or two away, so if the injectors are repairable that might be the way to go. I thought about swapping injector #2 with another one, but with all the work to remove the fuel rail, it is just as easy to clean them all first. I'll keep track of #2 and put it in a different cylinder upon reassembly unless it is replaced.

This seems like a huge miss.

Only takes a second to check resistance on the injector. Dirty or clogged injectors will almost never cause a complete failure of the injector to fire. It will fire in an odd pattern or too much/too little, but it WILL fire.

Trusting the holley harness is also a mistake. It's mass produced in china like all their other stuff and mistakes happen. They are well known to have bad crimps or swapped wires, which is why you should ALWAYS ring out any harness whether you made it yourself or got it brand new.

I would, at a minimum, make sure you have continuity between the "not red" wire at the Injector #2 connector and Pin 26 on the P1B connector at the Terminator PCM. If you don't have continuity(less than 2 Ohms), then you found your problem. Make sure you move the connectors around a bunch while checking it, because loose pins or damaged wires at the connector are also common.

The way high impedance injectors work is that you have constant power provided to the injector straight from the battery(hopefully through a fuse and ignition switched relay). The injector has a high impedance(12-16 Ohm) resistance to act as the load so the PCM doesn't see any voltage. The PCM then provides a ground signal to the injector to fire the injector. If that ground wire is not connected, the injector won't fire. If the injector is bad(internally shorted) the unregulated current will hit the driver and the holley drivers are not designed to handle that. It will burn the driver out and sometimes will cause the entire PCM to fault out. If the injector is bad(burned out so the connection is internally OPEN), then everything will ring out properly and the computer will be trying to fire the injector, but nothing will happen.

Before removing anything mechanically, you can check the main electrical components in about 5 minutes with a mutimeter.
1)Disconnect the injector connector from Injector #2
2)Check resistance between the two pins on Injector #2(should be 12-18Ohms). If it is not, full stop, you have found your problem and need a new injector.
3)Turn key on and check voltage between Injector #2 harness connector pins(should be 6volts on a stock PCM, probably same or 0v for holley) and from each pin to a good frame ground(one pin should be 12v and the other should be 0v)

 

[Bruce Wingate]

My working theory right now is that I have 1 dead injector and one or more leaky or stuck on injectors. Its running rich enough that there is raw fuel coming out of the tailpipe.

All the stuff you suggested is Part 2 that I will do if necessary and/or as I'm reassembling everything. In my mind, if I check the #2 injector and it is bad, I will still want to pull and check all the other injectors and check them for leaks/sticking/crud.

I think we're going to end up in the same place by the time everything is put back together. I've got my laminated wiring diagram ready to go so I can check the pins.

 

[Camar068]

Not sure what would happen if you installed larger injectors and it not tuned for them. Just a thought.

 

[Bextreme04]

My working theory right now is that I have 1 dead injector and one or more leaky or stuck on injectors. Its running rich enough that there is raw fuel coming out of the tailpipe.

All the stuff you suggested is Part 2 that I will do if necessary and/or as I'm reassembling everything. In my mind, if I check the #2 injector and it is bad, I will still want to pull and check all the other injectors and check them for leaks/sticking/crud.

I think we're going to end up in the same place by the time everything is put back together. I've got my laminated wiring diagram ready to go so I can check the pins.

I don't want this to sound like I am hammering on the Holley again... but this is probably not due to all of your injectors being stuck or clogged. This is almost assuredly due to the limitations in how "smart" the holley is.

Based on the way it is acting, I bet you have the single O2 sensor installed either after a merge or on the #2 bank? If so, that's why it is pig rich and its fully expected based on how the holley operates. It doesn't do bank specific fueling and it isn't fueling based on VE or airflow. It is using a very generic base fueling map for the cam size and displacement you tell it on initial installation. It then makes VERY BIG changes in the fueling map based on MAP and the wideband O2 sensor at initial startup to get the basic table learning at a reasonable baseline.

The way that an O2 sensor works is by looking at how much oxygen is present on one side of the sensor(in the tailpipe) compared to the other side(ambient). It doesn't see fuel at all. Since you have an entire cylinder full of un-combusted oxygen going to the sensor, it sees it as horribly lean and is trying to dump enough fuel to offset that. Since you STILL have the same un-combusted cylinder full of oxygen after it makes the change... it makes a change again... and again... and again. Until you have fuel dumping out the exhaust. Stop running it until you check your wiring and the injector. There is no need to remove anything mechanically until you do so. Continuing to run it with a possibly dead shorted injector could burn out the PCM.

I don't understand the aversion to not wanting to test anything. This is technician 101, verify everything. It is literally disconnecting one simple to access connector and 5 minutes with a multimeter to VERIFY whether you need to do any of the mechanical disassembly and cleaning you are talking about.

 

[Bextreme04]

Not sure what would happen if you installed larger injectors and it not tuned for them. Just a thought.

It's a holley Terminator, you program the injectors in at the initial startup by either GM PN or by entering the specific injector data. You can also change it at any time later on, then it does an initial learn of the fuel map when you first start it up. If you KNOW you have an injector not providing any fuel, it would be expected that the other cylinders are going to be getting flooded to make up for it since it is adjusting the entire fuel map based on the single wideband O2 sensor input. O2 sensor only detect O2, not fuel.

 

[Ricko1966]

It's a holley Terminator, you program the injectors in at the initial startup by either GM PN or by entering the specific injector data. You can also change it at any time later on, then it does an initial learn of the fuel map when you first start it up. If you KNOW you have an injector not providing any fuel, it would be expected that the other cylinders are going to be getting flooded to make up for it since it is adjusting the entire fuel map based on the single wideband O2 sensor input. O2 sensor only detect O2, not fuel.

I know nothing about the Holley Terminator system,but sounds like you do. Are the injectors batch fired,and are the injector leads long enough to just move the connector from cylinder 2 to cylinder 4 and vice versa? If the problem moves to 4 we know it's a wiring/pcm problem. If it stays on 2 it's probably an injector. I would have already tested for injector signal,that would tell the story.

 

[Bruce Wingate]

Why do I resist checking the ohms? Because I have terrible luck with connectors and no matter what I tend to break them. I felt that taking the fuel rails off would be easier because then I would have better access to the connectors.

But that' not what I did. It took about an hour but I got the connectors off and checked the resistance of all the injectors. They were all around 11.3 - 11.9 ohms. I feel this is low, but it is supposed to be within spec. I checked the injector harness for continuity and all the injectors were OK. I then reconnected the injector harness and tested continuity for a few injectors from the main connector at the CPU (?) to the injectors and they were ok as well. Shook the connectors and no changes.

I should be getting an injector cleaner "buzz box" in tomorrow and will test and clean the injectors. After everything is put back together, I will also test the injectors using the Terminator X which now allows you to trigger sensors (and the injectors.

Two things I found while poking around: the ground was not connected directly to the battery - that was fixed. Also, all my tunes were set up for the Terminator's internal MAP sensor, but that is not connected and the system is connected to the stock GM map sensor. I have to fix my tune.

Now I'm kind of lost. If the injectors are good and the connections are good, The only thing left is the plug wires.

 

[Bruce Wingate]

I know nothing about the Holley Terminator system,but sounds like you do. Are the injectors batch fired,and are the injector leads long enough to just move the connector from cylinder 2 to cylinder 4 and vice versa? If the problem moves to 4 we know it's a wiring/pcm problem. If it stays on 2 it's probably an injector. I would have already tested for injector signal,that would tell the story.

To my understanding, the Terminator fires sequentially and is not a wasted spark system. I swapped ignition coils with no change. Tomorrow or Monday I will use some of the diagnostic funtions of the Terminator to trigger the injectors individually and see what happens

 

[Ricko1966]

To my understanding, the Terminator fires sequentially and is not a wasted spark system. I swapped ignition coils with no change. Tomorrow or Monday I will use some of the diagnostic funtions of the Terminator to trigger the injectors individually and see what happens

Batch fire I was referring to injectors,they will either be batch fired,or selective fire. Batch fire they all spray at the same time.

 

[Bextreme04]

Why do I resist checking the ohms? Because I have terrible luck with connectors and no matter what I tend to break them. I felt that taking the fuel rails off would be easier because then I would have better access to the connectors.

But that' not what I did. It took about an hour but I got the connectors off and checked the resistance of all the injectors. They were all around 11.3 - 11.9 ohms. I feel this is low, but it is supposed to be within spec. I checked the injector harness for continuity and all the injectors were OK. I then reconnected the injector harness and tested continuity for a few injectors from the main connector at the CPU (?) to the injectors and they were ok as well. Shook the connectors and no changes.

I should be getting an injector cleaner "buzz box" in tomorrow and will test and clean the injectors. After everything is put back together, I will also test the injectors using the Terminator X which now allows you to trigger sensors (and the injectors.

Two things I found while poking around: the ground was not connected directly to the battery - that was fixed. Also, all my tunes were set up for the Terminator's internal MAP sensor, but that is not connected and the system is connected to the stock GM map sensor. I have to fix my tune.

Now I'm kind of lost. If the injectors are good and the connections are good, The only thing left is the plug wires.

Grounds are a big one. Did you check the voltage as well at the connectors? Continuity is a big one, but voltage to the battery is also very important. Grounds from the Terminator back to the battery are also very important. Bad connection will increase the resistance and can cause damage. There are a lot of things left other than plug wires that could be wrong. You could have a bad PCM as well. I would say that your next step would be to check voltage at the connector, then connect a noid light as suggested by Ricko. If you trigger the terminator to fire that injector and the noid light illuminates, but no fuel comes out... you have a bad injector. For the record, I have never seen an injector completely stuck closed... but that doesn't mean it couldn't happen.

To my understanding, the Terminator fires sequentially and is not a wasted spark system. I swapped ignition coils with no change. Tomorrow or Monday I will use some of the diagnostic funtions of the Terminator to trigger the injectors individually and see what happens

You can select to have it batch fire if you want to, but the default injector firing in the Terminator for the LS is sequential.

Batch fire I was referring to injectors,they will either be batch fired,or selective fire. Batch fire they all spray at the same time.

The new Holley EFI systems are capable of four types of injection strategies:
• Bank-to-Bank ― Fires half the injectors and then the other half every 180 crankshaft degrees (injectors fire once per revolution).
• Untimed Sequential ― Fires each injector every 90 degrees. But since there is no cam sync signal, it is random which cylinder is first triggered.
• Paired ― Similar to Bank to Bank, except only two injectors are fired at a time (fires a pair of injectors every 90 crankshaft degrees).
• Sequential ― Fires the injectors in sequence of engine's firing order (requires cam sync sensor).

 

[Bruce Wingate]

Spent this morning cleaning/testing the injectors. All 8 injectors fire nicely with a good clean pattern.

Also spent some time at Youtube University trying to get some hints. I came up with two Scanner Danner videos:

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Like @Bextreme04 said, SD said to check voltages of the connections in sections. Also will set up a noid light on the even cylinders. I really did not think you could pull the injector lead off with the engine running, but the videos show you can.

I'm still a bit confused about where/how to get power and ground during sections of the test. Once I have a better formed question, I may come back with the question or for confirmation of what I think I should do.

Its too cold to work outside today and its going to be snowy and rainy tomorrow. I might not get to this until Wednesday or Thursday.

Thanks to everyone for their help!

 

[Bextreme04]

Spent this morning cleaning/testing the injectors. All 8 injectors fire nicely with a good clean pattern.

Also spent some time at Youtube University trying to get some hints. I came up with two Scanner Danner videos:

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Like @Bextreme04 said, SD said to check voltages of the connections in sections. Also will set up a noid light on the even cylinders. I really did not think you could pull the injector lead off with the engine running, but the videos show you can.

I'm still a bit confused about where/how to get power and ground during sections of the test. Once I have a better formed question, I may come back with the question or for confirmation of what I think I should do.

Its too cold to work outside today and its going to be snowy and rainy tomorrow. I might not get to this until Wednesday or Thursday.

Thanks to everyone for their help!

Well, I can't say I'm surprised... but I'm sad that it came to this. It's definitely the worst case in my mind.

Power for the injectors is a single pin through the injector connector direct to the main power relay. The odds of a single injector not getting power are low and would be isolated to the injector harness itself between the #2 injector and the injector harness connector. You will want to check for power between the power pin on the injector connector and the battery ground. If you don't get a voltage signal doing that, move to where the Holley harness grounds are connected. If you don't get voltage at the battery but get it at the holley harness ground, then you have a grounding issue. Power will be constant at the injectors with key on. The PCM will be activating a ground on the other pin in the injector connector to fire the injector. You should be seeing an alternating continuity to ground on that pin as the engine is cranking.

The more likely problem would be one of two things. It's going to be either a wiring harness issue between the ground pin on the #2 injector connector and the correct pin at the terminator, or worst case the terminator has a bad injector driver. It's unfortunately not an unheard of problem for holley. Document everything you are doing and hopefully you haven't done what I have been know to regularly do and purchased the holley long enough before installing it that any warranty has already expired. If you check the harness and find that the connection from the injector to the PCM is in the correct position and has continuity throughout, then it MUST be a bad PCM driver.

 

[Bruce Wingate]

Spent today putting the fuel rail back on and everything buttoned up. I put a noid light on the even cylinders and got a positive result for all four cylinders (flashing lights = good). I tried checking to see if the injectors were clicking with a screwdriver, but couldn't quite tell - I heard what sounded more like a whooshing sound in all eight cylinders. I'm going to try again with a stethoscope tomorrow.

I also spent some time getting the USB/PC connection up and running. I corrected the set up so that the correct MAP sensor was selected (previously, the internal MAP sensor was selected, but that was not connected). After fixing the MAP sensor, the truck still runs rich and seems to run better for maybe a minute and then starts to run rough, shake and eventually stalls. It sounds like it is "chugging" before it stalls. If I give it some gas, it would run a little longer, but I did not like how it sounded. It still blows white smoke with raw fuel, just less smoke.

With a good result from the noid lights and injectors that tested good, I'm thinking that my problem might be spark instead of fuel. Once the noid lights came back OK, I did not think that chasing down voltages and shorts in the injector circuit would be worthwhile. That may change after I check spark.

 

[Camar068]

With a good result from the noid lights and injectors that tested good, I'm thinking that my problem might be spark instead of fuel.

Might try an old school timing light on each spark plug wire and wiggle wires. Just a thought.

 

[Bruce Wingate]

Might try an old school timing light on each spark plug wire and wiggle wires. Just a thought.

I thought I replied to this a few days ago - guess I didn't hit send. I tried this and it didn't work. Its either my cheap timing light or I screwed it up.

Today I hooked up a spark plug checker on cylinders 2, 4 and 1. All flashed appropriately although #1 seemed a little brighter. So now I have fuel, compression and spark but no fire. That just can't be right.

I unplugged the #2 injector and the engine ran suprisingly well. It starts out a little rich but settles into to around 14.x fairly quickly. I used a stethoscope to check the injectors except for #2 on the even side and they all clicked pretty well. As soon as I plug #2 back in, the engine shudders and dies pretty quickly - typically before I could get the stethoscope on it.

I'm going to try to switch the #2 and #4 injectors and see what happens. Hopefully the problem follows the injector.