Jump to content
HybridZ

posting my .msq, pleaseeee help getting it running


jimbo5670

Recommended Posts

The setup

82' l28et

stock turbo

stock boost

stock injectors

32 lbs of fuel pressure with a walbro 255

the ignition is a crane cams xr700 with the oilshaft and distributor from a 72' l24

no o2 sensor as of yet

 

the symptoms

no power

stumbles reallll bad (almost stalls) when you give it some throttle

pops when you rev it

 

my .msq

http://putstuff.putfile.com/57516/872258

 

if anyone can help, it would be awsume, i miss driving my z!!

 

thanks,

matt

Link to comment
Share on other sites

Your Injector Staging is set to "alternating" are you using two separate banks of injectors? I think, I think, I think, you should be running "simultaneous".

 

Your setup also includes corrections for O2 sensor. Might want to add an O2 sensor or figure out how to tell MS that you are not using one. You could just raise the activation temp to like 300degrees and it will never use the O2 settings.

Link to comment
Share on other sites

ok, its version 2.2, no ms n spark, spark is ran by the distributor and the crane module i had mentioned

 

i changed it to simultaneous injector staging and got the o2 up to high for actvation, put it on the road and gave it gas, still noooooo power what-so-ever

 

then i took the fuel map from moby's faq, tried it again, still no power

 

checked the timing, reading 15 at idle, should be enough to get moving, or could it be reading wrong?

 

and i have the accel numbers from moby's post, are they pertinate?

 

thanks guys,

matt

Link to comment
Share on other sites

First off... be happy you've got it so it will idle. It helps a lot when troubleshooting.

 

My questions:

1) Has the car ever run well using megasquirt

2) What are you using for throttle position? Turn on the throttle position guage in megasquirt and make sure that it reads 0 to 100% when you step on the gas.

3) Put the timing light on it when it is at idle and leave it there... increase the revs by turning the throttle body. What happens to the timing as the revs increase?

4) What brand of plug wires do you have?

5) Did you recently change the oil shaft - or has it run good since you changed the oil shaft?

6) What coil are you using? What are your dwell settings?

7) What kind of fuel pressure regulator are you running? Does the fuel pressure increase with revs?

 

I think that is it for now. I'll have more questions when you write back.

Link to comment
Share on other sites

ok, to anwser your questions

 

1) the car has not ran well sence i pulled the old l24, although it has good compression accross the boards, and burns no oil, currently is the best i have ever had it run with MS

 

2) the TPS is a 240sx one rigged to the stock 50mm throttle body, it goes from 0 - about 91 or so, my gas pedal needs some adjusting

 

3) at idle the timing sits at 15-16 deg advance, the dizzy still has a mechanical advance so itll do 19-20 at WOT and 4k rpm, then drop back down when i let off,

-by the way, the car shakes like my teeth are going to fall out at 1200, and then smooths out after 1700

 

4) the plug wires are crap, dono, picked em up at advance auto for like 20-25$, didnt think they made a difference? the plugs are ngk-whatevertheheck they recommend for l28et's

 

5) the story behind the oil shaft change is after i failed miserably at MSnS i decided to simplify things for the time being, pulled the 82' dizzy and oil shaft, lined the keyway up with the keyway in the 72' shaft and then put that dizzy/crane cams xr700 module in, messed with it till it read 15 deg advance, and by process of elimination figured out the firing order

 

6) the coil is the 240z one, actually i had not considered that till right now, it stays cool enough, and i ditched the ballist resister, she makes a nice big spark, but dono if that is bad or not, the xr700 has no programability, so i have no clue about the dwell, i assumed that it worked well on the old motor, ignoriance says it should work well in this case too, hah

 

7)the fuel system is this

240z tank stock feed --> 3/8 fuel line --> walbro 255 inline fuel pump --> generic fuel inj filter --> stock rails and injectors --> ebay special fuel pressure regulator, option for rising rate, but disconnected ATM, reading 32 lbs currently --> 3/8 fuel line --> return though one of the top vent lines

 

there you have it, all the rigs nessasary to keep the swap cheap/screw everything up, haha

 

one other thing, someone was mentioning that you need to ground the MS on the same wire as some sensor, or the injectors at the same place as the megasquirt, can anyone shed some light on this?

 

thanks for reading the long ramble,

matt

Link to comment
Share on other sites

Generally speaking - on most people's posts where they have the car idleing - the problem isn't with the megasquirt. I suggest checking the basics.

 

Start by pulling the #1 plug... while rolling the crank to 0 degrees of timing - check to make sure the #1 piston is coming up to TDC (and is at TDC when the timing mark is at zero). Leave it at zero and pull out the dizzy - check the orientation of the oil shaft. A picture can be found in the haynes manual or on this website:

 

http://www.atlanticz.ca/zclub/techtips/distributor/index.html

 

While you are at it - make sure you have the firing order correct.

 

With the engine running - put the pickup for your timing light on each wire and verify you are getting an even spark output to each wire.

 

The fuel pressure regulator thing caught my eye... I'm 99% sure the stock fuel pressure regulator is rising rate (it has a vacuum line hooked up to it). For this reason - the tables in Moby's sticky are likely given using a rising rate fuel pressure regulator. If you ran a non-rising rate FPR - and the tables in Moby's sticky - your car would likely be running very lean under throttle conditions. I'll look to some other hybrid members for some verification on this.

 

I've got some other things to check - but let us start here first.

Link to comment
Share on other sites

Despite anything that MSA will try to tell you, the XR700 REQUIRES a ballast resistor. I had that setup at one point in time and spent over an hour waiting for Crane tech support to tell me I needed a ballast resistor. Trust me, it will solve half the problem (if not more than half!). After that, it should just be a matter of getting the timing set...

Link to comment
Share on other sites

2) the TPS is a 240sx one rigged to the stock 50mm throttle body, it goes from 0 - about 91 or so, my gas pedal needs some adjusting

Don't try to adjust the gas pedal for more travel!! The reason it only goes to 91% is because your throttle linkage is worn and if you try to adjust the slop out of it you WILL end up with a runaway car at WOT (I know this from experience, luckily I was able to shut it off wiht the key and re-adjust the linkage back the wya it was...especially since stock Z brakes are NOT capable of stopping the torque from a boosted L28 at WOT on the boil in first gear...it overpowers the rear brakes and the front wheels lock and slide...scary stuff!)

In fact your linkage is actually pretty tight compared to mine, I can only get 75% throttle form inside the car, unless I boot it, let up and BOOT it again.

(in which case I can get up to 99% [actual throttle blade travel] for a few seconds...)

If you want you can recal the TPS so it goes from 0-100% with existing gas pedal travel, this way if you boot it hard and actually get 100% throttle it will go to 109% and still calculate the required fuel. This is how mine is set up, inside the car, gradually pressing to the floor will give my 0-100% in megatune(but the throttle blade only opens 3/4 of the way), but under the hood I get 0-125% (since I can actually open the throttle all the way under the hood)

I guess this really won't affect the driveablility of the car, but since the flood clear threshold is somewhere around 70% or so, I thought it would be prudent to fool MS into thinking the throttle is open all the way when it's pushed to the floor in the car (while cranking) so I can clear a flooded engine. (which actually happens often, I still have to calibrate my cold start mixtures, but until I fix the throttle problem the cold-starts will be difficult because the sloppy linkage means the throttle never returns to the same place when the throttle is released.) Anyone have any successes on fixing this without welding and such please enlighten me :)

Please chime in and let me know if this is how I should be doing it or if I should calibrate the TPS using the full travel of the throttle blade itself and not the available travel from the gas pedal?

Link to comment
Share on other sites

Yep ballast resistor goes between coil power (black, white stripe) and pos side of coil. The trick is the power wire for the ign unit (red?) goes to the harness side of the resistor. I believe it says somewhere in the manual what size resistor you need, but the stock S30 one should work fine.

 

On another note, THANKS TWOEIGHTYTHREEZ FOR THAT INFO! That would explain my runaway motor problem. If I step into the throttle and the turbo spools up quickly, it sucks the pedal to the floor. I will have to re-adjust that...

Link to comment
Share on other sites

YEEEEEEEEEEEEEEEEEEEHAAAAAAAAAAAAAAWWWWWWWW!

 

she runs!!! after so many hassles, it was the f***ing firing order, if i wasnt so excited i would be pissed at myself. Get to drive it tommorow for the first time sence August, it'll be tough to get to sleep tonight.

 

cant thank this forum enough for the help,

matt

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...