MSefi.com read only forum (Jan.15,2018)

Can anyone help me? Im trying to convert my Toyota 22r to EFI (ive tried twice now with the Megasquirt)

Im using the DIYPnP ND42, factory manifold, 195cc injectors (stock), factory clt, gm open iat, factory coil with either the 22re locked dizzy or the 22r vac advance dizzy (tried running fuel only), AEM wideband o2.

Everything bench tests fine and i even have a map from another user running the exact same engine setup. All the wiring is fine as it's the factory loom with the main earth to the block and an additional earth tho the firewall.

The problem is i have fuel and spark but i cant get it to run, the best i had was a single cylinder running for a minute or so with 30% throttle.

When i put the carby back on it starts first crank.

Can anyone give me a suggestion? I m getting fast at doing the conversion, but thats not really a skill i want.

Thanks
Mitch

While the tune looks rough, it doesn't look like an obvious no-start tune, either. I would like for you to check the spark timing to be sure it's happening at a reasonable point, and check the spark plugs after a failed start to see if they're wet (too much fuel) or dry (not enough). Also, if you could post a data log of an attempted start, that would also be helpful.

Unfortunatley i didnt make a log or pull the plugs, however the AFR reading went from 18 to 10 as soon as i started cranking and i had a strong smell of petrol from the exhaust. Could that mean i was too rich? Spark timing was spot on.

What do you mean by the tune looked rough? in what areas should it be "worked on"

Thanks

aussie22r wrote:Unfortunatley i didnt make a log or pull the plugs, however the AFR reading went from 18 to 10 as soon as i started cranking and i had a strong smell of petrol from the exhaust. Could that mean i was too rich? Spark timing was spot on.

What do you mean by the tune looked rough? in what areas should it be "worked on"

Thanks

The usual way when starting from scratch is to alter the 'required fuel' setting until you get a reliable idle. At say about 14:1 with the engine hot. This alters the fuelling across the entire range, so if the map your using is basically near enough, you should then find it runs reasonably at all speeds.

But you must read the manual. And make sure it's for your version of MS. Use the calculator to find out what your 'required fuel' setting should be. The actual one you use to get it running shouldn't be far out from the calculated one.

My (limited) experience of MS - starting from scratch with the only help being the manual - is that it's quite easy to get the engine running pretty good. Fine tuning for decent economy etc is what takes the time. Lots of it. ;-)

aussie22r wrote:Unfortunatley i didnt make a log or pull the plugs, however the AFR reading went from 18 to 10 as soon as i started cranking and i had a strong smell of petrol from the exhaust. Could that mean i was too rich? Spark timing was spot on.

Usually it takes a while to warm up the O2 sensor enough to get a reliable reading. However, it's pretty clear if the timing is spot on that the problem is the fuel.

What do you mean by the tune looked rough? in what areas should it be "worked on"

Thanks

The VE table has a sharp peak right above idle, drops into a valley at around 2200 RPM, then builds to a second peak around 4000 - I've never seen an engine have two wildly separate peaks in its VE like that.

15 degrees of total timing at full throttle seems way too low. I've seen turbo 22REs running more timing at 8 psi of boost.

Bottom line, it looks like it needs some work, but first get the thing to start and idle.

So where would an experienced tuner go from here? Im really not sure what values to change to lean out the motor during start up.

aussie22r wrote:So where would an experienced tuner go from here? Im really not sure what values to change to lean out the motor during start up.

When RPM is below the cranking RPM, the pulse width comes from the cranking pulse width table. It then switches to this equation:

Pulse width = Required Fuel * VE * air density correction * (WUE+ASE) + other adjustments

As the engine warms up, ASE first turns off, then WUE tapers off to 100%. If it runs poorly when hot, adjust VE; if it only has trouble cold, use WUE and ASE.

Ive done some tinkering with the VE table and some other settings.
Does it look better or is it really much of a muchness?

Thanks

aussie22r wrote:Ive done some tinkering with the VE table and some other settings.
Does it look better or is it really much of a muchness?

Thanks

Please explain why you turned off ignition control.

I have taken ignition controll off so that I can get it started with fuel only. When I have it starting and ildling ill change the dizzy and igniter over.

Well, that was the only thing that jumped out at me as really weird in the tune.

So that's a good thing? I used the ve table generator to get that table and I lowered some of the wue & ase enrichments, not much though.

It looks more "normal", but if it isn't starting, it must ipso facto not be "right".

What is your throttle position? Try it completely closed and see if there are any signs of life. Too much air at idle won't work.