Twin Cam GT Bellett

[Jayme]

hey, I noticed from your log that it has detected a 6 cylinder memcal, that will cause it to misfire a bit as it is firing the injectors once every 3rd reference pulse, not once every 2 like a 4 cylinder needs. reset the jumper on your nvram to 4cyl mode, and also remove a little bit of fuel from your injector rate and till run like a dream compared to right now.

[65bellett]

That is awesome Jayme. I will charge the lap top and head out to the shed for some more logging

[Holden202T]

The shiny bit in the end of the sensor should cross the wheel straight, eg if you are looking downwards at wheel ======|===== where | is the notch, then the shiny bit in the sensor should also be aligned |

At the moment yours looks a bit /

Thats what i was trying to point out!

[65bellett]

Hi Guys I am a little bit confused. I swapped the NVRAM jumper from 6cyl to 4cyl and I have backed off the fuel ratio and I have not seen any real improvement. It is actually a little bit harder to start.

I took it for a drive around the block and then checked the log and it looks to me like it is now in 8cyl mode. Here are a few pics and the log. What am I doing wrong??

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[festy]

That log shows a 4cyl memcal detected, but it also shows a TPS stuck error code...

[65bellett]

Cheers for that Festy. I don't know where I read 8cyl. I will have to pull the tps and have a look at it.

[VL400]

The memcal type wont show correctly until the engine is running - the default is 8 cyl. The ECU only reads the data byte with memcal type when it gets a reference pulse. Might have looked at it before the engine started

You will also need to reduce the cranking fuel tables a bit now the injectors fire more often, this will fix the hard to start issue - the kinjflow item does not change cranking fuel, only running mode fuel.

[Jayme]

your biggest problem is still your crank trigger..... that thing needs to be rock solid. see all those sawteeth in your rpm trace, thats the crank losing sync. it shoudl be a dead smooth line

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on our datto, we had exact same problem, to solve it we put a big stay right out on the end of the trigger arm.

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[65bellett]

Ok so I have spent a couple of hot hours out in the shed re designing the bracket to hold the abs sensor. This time I have changed the way that it bolts to the timing cover and I am going to take some advice from Jayme and make a big heavy brace to support the tang that the abs sensor bolts on to. While taking a break I decided to give the ABS sensor a clean and spray the plug with a bit of contact spray and I discovered this.

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I can't imagine that this was helping the situation. So I am off to Pinch a Part tomorrow.

[65bellett]

Ok so yesterday I had what I thought were great plans. I decided to rebuild the bracket that was going to hold the ABS sensor and in turn move where the sensor was going to sit so that I could brace it from all angles and make sure wasn't going to get any more of that dam vibration that is giving me all of this grief.

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The pic above is the revised bracket and the big black X at the bottom is where I was planning on moving the sensor to. Now being the forward thinking bloke that I am it wasn't until I had already started making the bracket and planning the new position that I thought to ask "Is the new position going to affect the timing?". Well the answer was yes and as a bottom pulley for a twin cam Isuzu motor isn't that common I was forced to go back to the original position with no room to move and no where to brace it. As you can see from the pic by the time I put the fan belt on the sensor is right in the middle.

Here is the finished product that I ended up with

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I have also widened the notches in the bottom pulley made sure the sensor is centred down to the mm and it is sitting an even 2mm off the pulley. The car is almost drivable but I seem to be getting another error code

Here is the log any help would be appreciated