wideband reading lamba

[kingtal0n]

Did you verify the injector wiring by disconnecting the cylinder while it is disabled to make sure it was the correct cylinder, trace the wiring. You could also try flipping the harness 2 and 8 around to see if the disable injector test 'fixes' itself. If you modified the harness you will need to continuity test the injector plugs. I can explain how to do that if it comes to it.

condition of the plugs is all over the place. Will need to see compression test result. If the compression is even I would say your injectors are not equally distributing fuel. Or there is an air leaking to a manifold port.

[kingtal0n]

Careful when handing the plugs that you don't touch them and smear the carbon up. Then we can't read them correctly.

I advise use disposable clean new gloves when handling spark plugs. Don't try to tune the engine on expensive iridium plugs either. Its too late now but in the future don't waste the money, tuning will mark them all to hell and you will need fresh iridiums at the end of tuning anyways. For now its fine, they are clean enough they wont misfire. You are lucky the engine is running nice and lean it saved them. But they are too varied in condition, something is going on with fuel or air delivery/compression.

[kingtal0n]

You can press "print screen" on your keyboard, then open "MS PAINT" (just type 'paint' into the start menu) and Then press PASTE

It will paste a copy of the screen shot you take. You can save the file as a .JPG and upload it. Or continue using youtube its fine. Im just giving you options whatever is easier.

Here is your plugs please verify I have them label correctly


#2 looks the best. See the top of the electrode is nice and clean. The plug isn't stained brown. A small dark mark is normal its barely visible. A tiny bit of oil is normal.
#6 is the worse, filthy. Tiny flecks of hard carbon appear baked into the center white. Either due to handling or engine sitting carbon buildup getting hard then flaking off.

This is why we don't use iridiums right off the rip. Start with cheap plugs. Get many run time and mileage on the engine and oil changes and fully tuned. Then switch to iridium at last.

If the engine sat a while it may have poor valve sealing which will be demonstrated by compression test. It is odd that #2 has a good clean white plug but disabling that cylinder makes the engine go so lean. Could you have accidently wired 2 and 8 together so that disabling one of them causes both of them to turn off? I think you may be looking at something in the wiring. But I am getting ahead of myself we need a compression test just for general well being anyways.

[Jacog]

Did you verify the injector wiring by disconnecting the cylinder while it is disabled to make sure it was the correct cylinder, trace the wiring. You could also try flipping the harness 2 and 8 around to see if the disable injector test 'fixes' itself. If you modified the harness you will need to continuity test the injector plugs. I can explain how to do that if it comes to it.

condition of the plugs is all over the place. Will need to see compression test result. If the compression is even I would say your injectors are not equally distributing fuel. Or there is an air leaking to a manifold port.

I?m pretty sure the wiring is correct, I didn?t mess with it when trimming the harness that section still has the original loom, I don?t even removed it but I?ll cheack tomorrow doe, it get dark fast here in Texas and I don?t got light equipment

[kingtal0n]

Maybe a noid light will help. It shows injector pulse with a small light on the plug. I don't use them but you might find it helpful.

You could Check continuity between cylinders 2 and 8 injector plugs, do you know how to do that? The positive wires will have continuity the negatives will not. Should not.

Regardless- perform this type of test below:
with the engine running, disable injector #2, then unplug injector number 2 and listen to the engine change or not. It should not change. Perform the test carefully watching RPM with the scanner to confirm the RPM drop if there is one.
Then, While injector number 2 is unplugged, also unplug number 8 and listen to the engine change. It should noticeably RPM drop with number 8 unplugged.

Then, repeat this test but number 8. Disable #8 and then unplug #8 and make sure nothing happens when you unplug#8.
Then while #8 is unplugged, also unplug #2 and verify the RPM drop in the scanner with #2 unplugged.


You are confirming whether #2 and #8 have any connection and whether the injector wiring actually goes to the correct injector.

[Jacog]

You can press "print screen" on your keyboard, then open "MS PAINT" (just type 'paint' into the start menu) and Then press PASTE

It will paste a copy of the screen shot you take. You can save the file as a .JPG and upload it. Or continue using youtube its fine. Im just giving you options whatever is easier.

Here is your plugs please verify I have them label correctly


#2 looks the best. See the top of the electrode is nice and clean. The plug isn't stained brown. A small dark mark is normal its barely visible. A tiny bit of oil is normal.
#6 is the worse, filthy. Tiny flecks of hard carbon appear baked into the center white. Either due to handling or engine sitting carbon buildup getting hard then flaking off.

This is why we don't use iridiums right off the rip. Start with cheap plugs. Get many run time and mileage on the engine and oil changes and fully tuned. Then switch to iridium at last.

If the engine sat a while it may have poor valve sealing which will be demonstrated by compression test. It is odd that #2 has a good clean white plug but disabling that cylinder makes the engine go so lean. Could you have accidently wired 2 and 8 together so that disabling one of them causes both of them to turn off? I think you may be looking at something in the wiring. But I am getting ahead of myself we need a compression test just for general well being anyways.

2 and 4 are switched, and yea ima do the compression test Tomorrow I got the tool already

[Jacog]

Ok will definitely do this too I get it now. I just broke one of the plugs so I’ll have to buy a new one.

[kingtal0n]

Ok will definitely do this too I get it now. I just broke one of the plugs so I’ll have to buy a new one.

Buy 2x Sets of stock COPPER cheap plugs. NGK should be like $2/each Only use NGK

When the engine is mechanically electrically sound we tune on the first set.
Then we install a second set to verify the condition of the plugs after mileage.

Tuning will mark up the plugs making them impossible to read. Marks are OLD news from OLD tuning sessions we don't care about anymore so we get rid of them using a NEW set of plugs once the engine is fully tuned. Then, we drive the vehicle many miles 2000 to 12,000 miles to make sure they stay looking great. Then, finally, brand new iridium plugs go in once and for all now it can go 100k miles no issues.

DO NOT touch the brand new spark plugs with your human hands. It will leave residues, carbon, salt, debris, which bake on causing marks. Use DISPOSABLE CLEAN NEW gloves for handling spark plugs.
Do NOT use anti seize on the first set of plugs for tuning. Residual oil in the threads will prevent seizure in the short time we use them. On the FINAL set of plugs we can use a tiny bit of anti seize but applied very carefully using gloves WAY away from the ends.

[Jacog]

Wich ones would u say I should ge 217B92E2-B6C7-4DE9-B63D-032B5D8D0BDA.pngABD3E0D7-7F49-43CE-8592-940DA40B488C.jpg70D089B3-382E-4C0E-81A2-72B9F2FDDDAD.jpg

[kingtal0n]

Also take a look at the other side 1 3 5 7 see if they have the same kind of appearance or if they look much cleaner. Since you need to remove all plugs anyways to do a proper compression test.

Put the battery on a charger before you do the compression test. Don't let the battery run down while cranking. You only need to 'hit' each cylinder 3 or 4 times for a compression test. With all the plugs out will make the engine easier to spin and help the test. Make sure to charge the battery also after the test is finished. Dont let it run down too much in general its not good for lead acid batteries.

These are precautions in general. Sometimes i work on high compression 13:1 engines so the battery needs to be absolutely fully charged and the wiring must be large diameter and connected well. But the LM7 has low compression it won't be a tremendous drain to crank.

[kingtal0n]

TR5 NGK is stock heat range, always use NGK.

Here on ebay
eBay item number:304116408871

$22 for a set of 8

They used to be like 17

You can buy 1 or 2 sets. I can work with one set if you follow exactly what I said, e.g. don't touch them with your hands, use gloves, new clean dry gloves. And you tune the engine the way I say to over time. It won't mark them up too much.

[Jacog]

TR5 NGK is stock heat range, always use NGK.

Here on ebay
eBay item number:304116408871

$22 for a set of 8

They used to be like 17

You can buy 1 or 2 sets. I can work with one set if you follow exactly what I said, e.g. don't touch them with your hands, use gloves, new clean dry gloves. And you tune the engine the way I say to over time. It won't mark them up too much.

Ok I?ll get those. Also one question my purge valve dosent have the hose for it can that cause like a leak?

[kingtal0n]

I would need to see a picture of what you are talking about. Purge/Evap is an emission device I never used on any engine before most of what I work on is heavily modified and no longer has the original chassis and hoses to use that equipment. I believe it captures gasoline fumes into a activated charcoal canister and 'purges' them into the intake manifold when the vehicle reaches a certain speed and load to safely dispose of them if its what I am thinking of. It depends where the hose goes and whether it is normally open or closed, control by solenoid for example. Is it connected to the intake manifold somewhere? A pressure test can tell if the intake system is leaking its on my checklist. Do you need emissions on the engine? Is there some reason you left the purge valve on the engine but did not connect it? DO you plan to use it? If the ECU supports the function and everything is there I think you should use it because it can help with the gasoline fumes from the fuel tank. But I've never set one up before from scratch, like I am not sure what wire colors or how to change from one chassis to a different chassis on a new engine or whatever. Some slight difference in years can have big changes on devices like that.

If you don't need the "old" unused devices we can work on removing them and perform pressure testing to ensure the intake system is leak free

If you want to keep it we can work around it for now, make sure its not influencing anything, then after we tune the engine or almost done I will look up the service manual diagrams and figure out how to connect it properly for you and check the right boxes in the ECU. Pretty sure you will need charcoal canister under the engine bay intact and solenoid wiring plugged into somewhere on the harness for it to work. You said you re-worked the harness removed some wires- did you remove the purge wires?

[Jacog]

Also take a look at the other side 1 3 5 7 see if they have the same kind of appearance or if they look much cleaner. Since you need to remove all plugs anyways to do a proper compression test.

Put the battery on a charger before you do the compression test. Don't let the battery run down while cranking. You only need to 'hit' each cylinder 3 or 4 times for a compression test. With all the plugs out will make the engine easier to spin and help the test. Make sure to charge the battery also after the test is finished. Dont let it run down too much in general its not good for lead acid batteries.

These are precautions in general. Sometimes i work on high compression 13:1 engines so the battery needs to be absolutely fully charged and the wiring must be large diameter and connected well. But the LM7 has low compression it won't be a tremendous drain to crank.

For the compression test do I have to disable injection and the ignition system

[kingtal0n]

Disable Fuel Injection. You can simply pull/remove the fuel pump fuse. Or disable the fuel pump in the scanner "OFF" Red Color will appear on the button, make sure it turns red.
You could also unplug the crank sensor but that is much more work on an LM7 than the fuel pump.
Another option is remove the fuel line from the fuel rail. But again this is alot more work.

Spark doesn't matter you just don't want fuel going in there- washing the oil off the cylinder walls and leaking into the crankcase oil supply.

You can test the engine cold its fine. Cold AND hot, or just cold. If you want, warm the engine up, then do the compression test, then wait the next day and do it again for cold & hot. Its better data but I don't think we need to go that far right now.

Also a side note. With the scanner on a laptop running while you perform this test, Make sure the laptop does not move around during the test, secure it well, do not touch it or let it vibrate. Do not let the cables USB and HPtuners box/cables to move or vibrate. If you need to, wrap them in some cloth to secure them carefully away from vibration and heat if there is any heat.
And if possible, use the laptop's battery power (unplug the laptop from the wall charger during this test). Its just a precaution.

[Jacog]

Disable Fuel Injection. You can simply pull/remove the fuel pump fuse. Or disable the fuel pump in the scanner "OFF" Red Color will appear on the button, make sure it turns red.
You could also unplug the crank sensor but that is much more work on an LM7 than the fuel pump.
Another option is remove the fuel line from the fuel rail. But again this is alot more work.

Spark doesn't matter you just don't want fuel going in there- washing the oil off the cylinder walls and leaking into the crankcase oil supply.

You can test the engine cold its fine. Cold AND hot, or just cold. If you want, warm the engine up, then do the compression test, then wait the next day and do it again for cold & hot. Its better data but I don't think we need to go that far right now.

Also a side note. With the scanner on a laptop running while you perform this test, Make sure the laptop does not move around during the test, secure it well, do not touch it or let it vibrate. Do not let the cables USB and HPtuners box/cables to move or vibrate. If you need to, wrap them in some cloth to secure them carefully away from vibration and heat if there is any heat.
And if possible, use the laptop's battery power (unplug the laptop from the wall charger during this test). Its just a precaution.

alr so this is the compression test.https://www.youtube.com/shorts/43ceD...?feature=share

[Jacog]

This is the evap that dosent have the little hose and I found that other hose had a riphttps://youtube.com/shorts/ptVvOoXqV...huRRHSFaZ1li8U

[kingtal0n]

To see whether the broken plastic device is leaking you could put compressed air into it or perform a pressure test on the intake. You did not answer my questions about your plan to use it or not or where the wideband is located yet.

I think you can buy a block-off-plate for it if you don't want to replace it. Decide now, replace it or block it off, don't leave broken parts on the engine.


The broken hose does not surprise me, some old hoses break easily its not your fault just replace it. The engine should be cleaned up and replace the PCV system components and hoses. PCV is the most important system on the engine. I recommend install a factory air filter and factory PCV new hoses to the engine. You should clean the engine up remove the leaves and wash it a little bit after you replace any broken hoses and parts. You can blow out the leaves and wipe the engine with some simple green or plain soap and water.


Please perform the injector disable/clip test and find the results from that. The compression is fine. It may be simple leaking or clogged injectors on 2 and 8. You should finish the rpm drop test to ensure the wiring is correct and there is no shorts. Then, if the wiring is good, you can move injector #2 to cylinder #1 and injector number 8 to cylinder #6 and see whether the problem follows the injectors to confirm the issue is that the injectors need to be serviced. Also look at the part numbes on the injectors and make sure they are all identical. While the injectors are out maybe you can also inspect the fuel rail inside for debris.

[kingtal0n]

Maybe this is the block off? I don't use truck intake manifolds but it should be a simple thing to block off


https://www.amazon.ca/Intake-Manifol.../dp/B094MLDJWG


Also remember. Whenever you finished using a torque wrench, always release the spring, turn it back to zero or it will become out of calibration.

The same goes for compression tester, never leave it full of pressure. Always relief the pressure when you are finished before putting it away.

Just making sure you knew these things.

[Jacog]

To see whether the broken plastic device is leaking you could put compressed air into it or perform a pressure test on the intake. You did not answer my questions about your plan to use it or not or where the wideband is located yet.

I think you can buy a block-off-plate for it if you don't want to replace it. Decide now, replace it or block it off, don't leave broken parts on the engine.


The broken hose does not surprise me, some old hoses break easily its not your fault just replace it. The engine should be cleaned up and replace the PCV system components and hoses. PCV is the most important system on the engine. I recommend install a factory air filter and factory PCV new hoses to the engine. You should clean the engine up remove the leaves and wash it a little bit after you replace any broken hoses and parts. You can blow out the leaves and wipe the engine with some simple green or plain soap and water.


Please perform the injector disable/clip test and find the results from that. The compression is fine. It may be simple leaking or clogged injectors on 2 and 8. You should finish the rpm drop test to ensure the wiring is correct and there is no shorts. Then, if the wiring is good, you can move injector #2 to cylinder #1 and injector number 8 to cylinder #6 and see whether the problem follows the injectors to confirm the issue is that the injectors need to be serviced. Also look at the part numbes on the injectors and make sure they are all identical. While the injectors are out maybe you can also inspect the fuel rail inside for debris.

alr so i bout the block off plate for the evap, the new spark plugs just got here and i just installed them. the wide band is located in the driver side of the long tube where the narrowband should off when to, and on the passenger side i have a narrowband. the hose i replaced it with one i had laying on a other engine but it still had a rip inthe same place but it was smaller so im testing it out. i did another injector test, all of them read about the same but their all inthe 18,19,20s