Tmanlad

Hi all!

So i'm new here and new to the tuning scene. I've been undergoing a turbo conversion on my 97 1.8 and everything has gone great up untill the point of turning the whole thing on with MS!

Here are a few details about the build:
GM IAT sensor
440cc rx8 injectors
t25 turbo
aem gauge with lsu 4.2

I've managed to hook my laptop up to the MS and put on a base tune to get it going but when I switch on the ignition all the engine does is turn over and not fire! I am aware there are many threads relating to this but cant find a definitive resolve. Any help would be great!

I will attach my tune. I would of done a log aswell but my battery died before I could (purchasing a charger tomorrow).

Thank you!

rndmheroxx

iTrader: (1)

Awaiting tune... However you deffinitely are going to need to pull a plug and check for spark while cranking also. We will assume you are getting fuel, map will tell us how much lol.

Please tell us which megasquirt you have also!!! Mspnp , diy 1,2, 3??

Also, you would be fine to plug in the stock ecu and check to see if it fires up just to eliminate any issues with the turbo install. Obviously don't drive or rev it up or anything. Just see if it starts on stock ecu.

Tmanlad

Appologese for the late reply, I've been at work all day where i have no signal :/. Sorry about the lack of detail.

It's a MSPNP2. I have been emailing Phil from diyautotune and he wants me to sort out the timing and then get back to him but i will attach the tune, datalog and composite log.

Phil tells me i'm not getting a cam or crank reading. Does any of this sound familiar?

Thanks for any help.

Tmanlad

Quick update: I just started it with the stock ECU and it felt like a cylinder wasn't firing. I found cylinder 3 injector was leaking (seemingly, quite a bit). I shall resolve this (i have spare o-rings if needed), restart on stock ecu and get back to you.

Tmanlad

Another update: I resolved the leak with the fuel injector, retried with the stock ECU but didn't completely start this time (definitely fired a few times). After that I plugged the MSPNP back in and gave that a go. It started up first try no problem! It sounded great and then after a few seconds the engine cut out. I tried a few times to start her up again but to no avail.

My assumption is that fuel pump doesn't start on the MS. Trying a start up with the stock ECU gave the fuel system a nice load of fuel, so when i tried starting with the MS it was running of of what was left from the stock ECU and then cut out due to starve of fuel.

What are your thoughts on this?

rndmheroxx

iTrader: (1)

Deffinitely curious to see what your maps look like now. Do you have a wideband hooked up???

You can also jumper the fuel pump in the diagnostics box under the hood I believe. If you want to rule that out easily, just jump it, and see if it will fire again on the megasquirt. Although that sounds pretty unlikely to me that your MS is failing to turn on your fuel pump.give it a go!

Ben

iTrader: (33)

The odds of the MSPNP not being able to control the fuel pump are pretty low. Here are 2 diagnostic tests you can try:
(1) use test mode to command fuel pump on and off, with key on, engine off
(2) install a jumper between FP and GND in the underhood diagnostic box to force on the fuel pump

Tmanlad

Okay, thanks guys! I'll give those a try later on after work. Its just annoying I had it running for those few precious seconds.

Sorry buddy, did my tune upload to that post a few back? I attached a datalog as well.

Thanks for the help.

Tmanlad

Hi guys!

A bit of an update here for you.
I found i had wired the wideband output into the wrong pin but resolved that.
I jumped the fuel pump in the diagnostic box and voila, started up fine .
only 2 issues i have no is: 1 faulty fuel injector (or leaking seal) and why the **** is the fuel pump not running alone?!

I ran a datalog for a while whilst i had her running so i'll attach that if any of you fancy a look. Just to note, I changed nothing from the original tune.

rndmheroxx

iTrader: (1)

Did you purchase the MS second hand? Just curious.

But I would bet a fair amount of money on the problem lying in the harness, most likely at the edu connection.

Is it the stock fuel pump? Didn't upgrade for turbo? ( not that you need to )

We are deffinitely close to finding the issue, I suspect it's something silly at this point haha

Tmanlad

No, the fuel pump is stock and the mspnp is brand new from diy auto tune. This is rather puzzling indeed.

I'll go over the tune again tonight just to triple check I haven't put any stupid setting or missed andthing.

Tmanlad

Hi guys!

Some great developments today!! I have found on this thread on mx5nutz someone with the exact same car, ecu and problem (Help - Fuel Pump Not Arming With Mega Squirt - Forced Induction & N/A Power Mods - MX5Nutz Forum). Basically this guy found out, somehow, that the U.S and the U.k 9796 1.8's have slightly different wiring in their terminals. All I had to do was swap over 1U and 1V. Amazed that this detail has slipped through.

Thanks guys for the help and i hope this helps anyone with the same problem in the future!

Onyxyth

iTrader: (2)

Hmm, that's really odd. Might be something good to pass onto the diyautotune guys.

Tmanlad

Yeah, I've given Phil an email letting him know. Seems like something they should consider when building their products.