Maft Pro PTB solution

[grimreaper]

One of the options on the maft-pro is to use Enahnced TPS. This takes the TPS signal and sends it to the ecu like normal. Once a set threshold is crossed, it sends an altered TPS signal to the ecu. You can set the threshold by either RPM, BOOST or BOTH. How fast it does the signal switch is tunable as well.
Once I cross into boost I have the Pro feeding the ecu a WOT tps signal. Looking at the screen shots below you will see 2 that have AUX 1 (VF signal) dropping to 0.01V right after entering boost, this is the ecu getting the WOT tps signal. THe other two clearly show AUX 1 (VF signal) still present with a stoich AF ratio being demanded.

Due to the MAP conversion, I've obviously mucked with the afm signal enough to get 5-6psi in closed loop. Timing is the same at the given points from closed loop to open loop as well.

So far this has been working like a charm, I'll update over the next few days as I get the tune nailed down. YAY, PTB with some control over AF ratios!

 

[clifspencer]

Is this the only way you have gotten maftpro to go into open loop for PTT?

 

[CajunKenny]

This is not part of PTT. It is ETPS. With ETPS configured correctly, you still leave the PT management to the TCCS.

This is just configuring the Maft to go in to open loop when there is positive manifold pressure. The stock TCCS will allow you build as much as 4 psi or more (under certain conditions) before switching to open loop. ETPS takes care of that. As soon as there's boost...you're going rich!

 

[mhopemk3]

Nice work Grim! I know it has been awhile since we last spoke. I bought an old 90 Corolla wagon with 120K miles for $300 and drive it daily. I have been on FTT website but have a lot of catching up to do. I am still trying to find a fix. The issue is that AFR's when starting the car cold and throughout the first start are good. When you turn the car off and crank it back up the AFR's are 2-4 richer. Do you remember that issue?

Matt

 

[CarlosPTR210]

How can I do that modification?

thanks and regards.

 

[grimreaper]

I have a thread on fullthrottletech.com. Search it for indpeth setup and wiring. (quite easy once you getting working on it though.)

I have a stored code 41 (tps code) and i suspect its due to the ecu powering up with the pro and beating the pro to the punch. Didn't even realize i had the code until i checked it before pulling the bottom end lol! never noticed a difference when driving and never had the check engine light on at all!

Working on a way to power the pro before the ecu to avoid this. To much other stuff do to though so it will be a while before i fix it..

Matt, never solved this. It was apparent that the ecu wasn't going down with out a fight and if I've learned anything with piggy backs, the ecu always wins.. i tossed in the towel and gave up . the ETPS gave me what i really NEEDED, the lean cruise would just be a nice perk!