Wire guy

LQ4/LQ9 FI guys did you delete knock sensors?

I am going through my harness right now getting rid of egr, evap, a/c and non essential connectors that I won't need. Did any of you delete the knock sensors or do anything special to the sensors?

I know buick guys used to put a lot of sealant tape on them and also tape them on the outside with electrical tape to keep miss signals from vibrations.

Also my harness didn't come with the diagnostic port and check engine light wire. I have the cpu, the engine side fuse panel with just the engine side of the harness like injectors and sensors and trans harness. I think this is an '03 or '04 throttle by cable lq4 mototor

ls1_chevelle

iTrader: (9)

I would keep them. You dont rely on the knock sensors via a check engine light, you rely on them when tuning the car(data log). some get false knock, some dont. Its all in how you play with the sensitivity. If the tune is mild and there's race gas in the tank... pretty safe to say it wont knock(thus eliminating it being real knock) so you can then turn the sensitivity down.

Wire guy

Thanks for the reply I know that you don't use the knock sensors via the check engine light and didn't mean to confuse the two topics.

What I need to know about the diagnostic port and check engine light was is there part of the truck harness missing that I need to purchase or can I run my own wires and buy the plug to hook up a scanner/laptop for tuning and diagnostic checks?

Here is another question. I am running an ls6 intake and no egr, evap or a/c and plan on cutting these out of the harness.

Here is what I plan on keeping let me know if I am missing anything: TPS, IAC, MAF, Coolant Temp., MAP, Crank sensor, Cam sensor, plugs for coil pacs, injector plugs, intake air temp, o2 sensors plugs, VSS, other trans plugs, knock sensors.

Mudweizer

Check out this site: http://www.lt1swap.com

Has some cool info on what you are asking.

Wire guy

Thanks that helps a lot.

ls1_chevelle

iTrader: (9)

Do yourself a favor and ditch the maf and run a speed density tune.

garys 68

iTrader: (1)

Keep the knock sensors. I found on my LQ9 they sense knock better than I can and back down the timing with cheap gas.
If you didn't get the OBDII port, you can buy one with wire pigtails for about $12 from any efi supplier or on ebay.
All you need for SES light is a 12V led with ground going to the ecu pin.
LT1 swap is a good resource for what's needed. Your list looks pretty complete.

psiconversion

iTrader: (5)

We have the DLC ports for under the dash as a pigtail if you need them. Also, check engine light must be hooked up or you will go into limp mode.

LS1 Chevelle, why are you recommending speed density?

Jon
PSI

mrvedit

Technically the PCM should be tuned properly for speed density (i.e. the VE table(s)) whether you a running a MAF or not. Since the MAP signal changes faster than the MAF signal, this allows the PCM to anticipate what the engine needs. When the speed density tune is correct, running with/without MAF should be very little difference. You can often create a better intake system (e.g. a "Y" with dual filters) if you skip the MAF.

psiconversion

iTrader: (5)

MRVEDIT, not sure if that response was to me, but I agree speed density works well when tuned correctly. However, not sure why that was being suggested for this particular build. Unless you are making huge boost or you cant fit the sensor, I always like to keep it. Just my opinion.

Jon
PSI

ls1_chevelle

iTrader: (9)

I read "fi" as forced induction. That's why I suggested getting rid of the maf.

ls1_chevelle

iTrader: (9)

And knock sensors are an issue with our boosted engines. Some read false knock all the time on factory settings so the sensitivity needs to be played with. Others work just fine? Kinda odd but is normal when asking around

mrvedit

No, I didn't see your post until after mine was done. I just try to be thorough for the many people that read these posts; often due to Google searches.

LS1_Chevelle was very astute to notice that "FI" probably means Forced Induction. I know nothing about FI tuning and will therefore drop out.

Wire guy

Thanks for the replies when I said FI i really meant fuel injection as apposed to carbed.

I have been studding LT1swap.com and in emails back and forth with Brenden right now. It appears I bought a motor with a cable throttle body and a harness from a DBW truck.

My LS6 intake already has a cable throttle body and my stock 300 zx has a cable that fits and works so I don't really want to run DBW. Waiting on a response to see if this harness can run an IAC and TPS.

I am going to run boost sooner than later but may fire it up and drive it NA and with a 200 shot first. I think I may go ahead and get rid of the mas air it will save me some money. I am going to run e-85 with real meth injection. I may even spray a little with the turbo and meth injection to make things really cold.lol That way I can leave off idle and not worry about a transbrake and trying to make a bunch of boost at the line while staging. This way I can leave without hitting the tires so hard out of the gate. With a ZO6 cam and 2200 converter 4L80E in a 2800 lb car with 3:50 gears I think this thing will still leave plenty hard even with little or no boost.

psiconversion

iTrader: (5)

LS1Chevelle, roger that.

Wire Guy,
I would recommend you find a drive by cable harness if you are going to run drive by cable. DBW harness could be reworked, but may not be worth the cost and rework.

Jon
PSI