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New to this course, forum and tuning. Need a little help.

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What's up guys. I have a 2jz vvti engine converted into a singe 62/66mm turbo. I purchased a Haltech Sprint 500 so, I can get familiar with the software and try to tune it myself. Now, I've put on the software Injector size,(440CC) Trigger Angle (65.5) Home (36-2+4). I've put 15 degrees or a little more on ignition advance and I hit the target. Base fuel at idle, I've send close to 96% to 100% of fuel delivery hit close to target, and my car still idles rough. Anybody knows what cause this? and help me address this issue?. By the way fuel table is on VE. I've read that it can be the Intake air control valve, or bad injectors.


A little more information on the installation itself would help, are you running batch fire? Have you checked your ignition off set(trigger angle) is right? Have you pulled the plugs yet?

I had a supra in the other day and a bad wiring connection was stopping an injector firing, fixed the connection and it ran smooth as it should.

Thanks Chris. Ok, the set up is 2j vvti converted into a single precision turbo (62/66mm) running sequential firing with factory internals. The trigger angle is set to 65.5 and home (36-2+4) that's how i have it set up. Haven't pulled the plugs, but now that you mentioned it I will. I'm new to this whole mech and tuning stuff. What was the connection that was preventing it the injectors from firing?.

Thanks again man.

It was the wires running into the plug so one of the injectors wasn't getting a full circuit, this was identified quickly by pulling the plugs and one of them was dry.

You're jumping in at the deep end by trying to tune if you're also new to mechanics, just take your time and ask as many questions as you need, we're all here to help

Ok, so I'm going to go ahead and crank the engine make sure it gets a few turns, then check the plugs and see if any are dry correct?.

If you've ran the engine already then pull them and take a look.

Do you know what AFR you were getting?

Alright will do!. AFR 14.7.

But when I adjust the cells to match the Base AFR of 14.7. Wideband reads a rich mixture of 13.5 or so by increasing the cells about 95% to a 100%.

My mistake, when I adjust the fuel cells on the base map to target AFR, I have to adjust the cells to about 104% to 108% @500RPM's and @750RPM's 96% to 100% and it hits target. Now for ignition, I followed the instructions on the start up modules on the course and set ignition to 15 degrees from vacuum till 0 manifold pressure before adjusting fuel of course and the car started. Now it idles stays idling but it's not a smooth idle. I'm a continue studying the course and get a better understanding on things. Thanks for the help man, I appreciate it brother.

You can't be running a 6 cylinder sequential when the ECU only has 4 injector outputs are you firing all cylinders?

I'm not sure, I'm new to the tuning world man but, Haltech e-mailed me a generic map and I'm working with that. Now, I checked the output options of the map and is on sequential firing. How can i check if i'm firing all cylinders on the ecu?

The Haltech Sprint 500 only has 4 injector outputs?. I was told a

I can run that engine with that ECU.


It will be able to run the engine, just not in true sequential.

Have you converted the coils to individual coils or kept the stock coil with extra lead?

It seems (from Haltech's cryptic description anyway) that the Sprint 500 can control up to 8 cylinders on full sequential?


"with 8 channels capable of controlling fuel and ign..."

Edit: Nevermind. Comparing it to the Sport 1000 it seems it'll have to be semi-sequential.


"It is capable of controlling sequential injection/ign on engines up to 4 cylinders, or semi-sequential up to 8 cylinders."

However, the sprint makes no mention of controlling VVTI, yet your engine has this, so how are you controlling it? Or have you converted to fixed cam gears? If you have too much overlap at idle that can explain the rough running if it's not due to incorrect wiring of the batch-fire injection/ignition.

Just a thought.

Yea, they mentioned to me that the sprint 500 does not control VVTI. I haven't made any changes to the engine or any upgrades. Its all factory internals. I know by taking the course on here, that there's a table to control the VVTI on it. It's like for Honda's with v-tech correct?, that you have a set up table to tune when the engines goes into v-tech.

So, the problem for the rough Idle can be too much overlap?.

I purchased the sprint to get familiarized with the software and setting it up don't want to get ahead of myself.

What ECU's would you guys recommend for a beginner like myself?. Thanks for the help btw.

All stock Chris.

You honestly might be better off selling the sprint 500 and pick up the elite 750, then you can't run true sequential injection for few hundred bucks more. I can try to get you a deal since I'm a Haltech dealer.

Is your timing set right? You can set the JZ out and fire on an exhaust stroke, especially if your running the stock wasted spark ignition system.

I was thinking about doing that Tommy since the Sprint 500 does not control VVTI. How much would you sell me an Elite 750 for?

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