Getting aggravated, thinking MegaSquirt

[jonnymopar]

Ok, I still can't figure out what the hell the problem is with my injectors not firing. I've switched computers, no change. I've switched hall effect pickups, no change. I'll get one quick pulse when the key goes to ON, then while cranking, nothing. Spark is there, fuel pressure is there. No pulse at all. Nice weather is here and I want to drive this F-ing car! I've put enough work into it to deserve it!

I'm really sorry if this is a really general question... but how hard is MegaSquirt to get running? I know some people are already done it. Do you need a laptop while the car is running, or just to tune it? I've still got the crank sensor stuck in the block just as a plug for the hole, plus I've got at least a few 2.0/2.4 cam sensors kicking around. Not to mention the car already has a 3-bar MAP sensor in it. Does it use the stock sensors?

[john doe]

The laptop is only for tuning like any other stand alone. You don't even need a cam sensor with MS. The MS has it's MAP sensor inside the case and you run a vacume line to it. It comes with a 2.5 bar sensor but you can easiely upgrade to a 3 or 4 bar sensor. You can set up the board to use the stock coolant and air temp sensors on the 2.4/2.0 engines.

I would tell you to go ahead and get the MS2 ECU with the V3 board. Everyone that has switched from the MS1 says it is great.

[shelbyplaya]

i'm gonna be running MS2 on the V3 board. still gonna be a wile befor i get it set up and tuned.

[MachIIIRayzor]

Sounds like your close to being up and running, I spent a few days chasing a similar issue on my 16v hybrid.

What's your setup consist of, what wiring have you had to modify?
Are you using a HEP?
Any codes? Can you still pull codes?

I did use stock stratus 12ohm injectors the first time my engine started, so yes they will work.

[jonnymopar]

I am VERY close. So close it hurts.

My setup is a complete 2.4 with distributor on the side of the head. Injectors are SRT-4 Stage 1. I am using the stock hall effect pickup. Only wiring I had to modify was lengthening the AIS and TPS wires, add the charge air temp connector, along with just about making the injector harness from scratch. I've since taken every ounce of split loom and tape off of the injector wires so there are no secrets. Right now I've got a stock 1989 Turbo II computer in there just for diagnosis. I don't know if the custom calibrations from Cindy will give codes. Personally I've never used a custom cal before.

I checked continuity from the 6-pin injector harness connector all the way back to the 14-pin SMEC connector and everything checks out as far as the two injector driver circuits.

Again, what happens is, when I turn the key on, I'll get one quick pulse of the injectors. When I crank the car, there is no injector pulse and the car just farts for a second on the small amount of fuel that the quick little initial pulse put in. Spark is there, but it's kinda crappy. I've got my timing gun with the trigger zip-tied so I can lay it down and watch it from inside the car while cranking. It doesn't seem to have very consistent spark, but it's definitely there (hence the car popping and farting for a second before it dies again). Fuel pressure is around 35psi while cranking. I don't know if that's what it should be because I haven't messed with my AFPR yet.

I was messing with it again today and still I'm getting nowhere. The "16V electronic distributor adapter" is just about my only hope before I fork over half a grand for MegaSquirt.

[90TurboVan]

You didn't say if you had any codes. I'd check for good ground and +8 volts at the HEP connectors (Orange is +, black/blue is ground). You can turn the motor over by hand and verify that the other (not orange or black/blue) wire switches from + to ground. The pulse you see when turning the ignition on is a priming pulse, so you know the ECU can indeed control the injectors. Spark may not be very consistent while cranking due to the crank speed changing pretty rapidly during each revolution. Custom cals should give out codes being as they're based on the Chrysler code, my '90 Stage IV did.

[jonnymopar]

I'll double-check for codes tomorrow. I did check for 8V at the HEP plugs today while I was under the hood, and both plugs have 8V and ground at the proper pins. However, I didn't check the output wire for either pickup. I'll probably just pull the distributor out and spin it by hand with the key on to check the output pins.

[blown3.8]

jon where are you in SE mass??

seeing im in SE mass myself.

who is your machinist??

[jonnymopar]

Right next to Taunton.

As far as my machinist... I've been picking it up for the past couple years now. I started at my job as an electronics engineer. Two years later, I'm doing the electronics as well as machining parts for prototypes. I love it! Big money saver too.

[wayne]

Aren't SRT-4 injectors high impedence and all 85-93 turbo cars were low impendence injectors? That maybe your problem is the injector.

[jonnymopar]

Eh, I had come across that thought, but if I'm using high impedance injectors on the original electronics, the drivers only have to sink about a third of the current that the low impedance injectors use.

If you went the other way, say, installing Turbo II injectors in an SRT-4, then you'd likely burn out the injector drivers because they weren't designed to supply the high current that the low impedance injectors use.

If my reasoning is wrong here, someone please correct me.

[blown3.8]

suprised i havent seen u around. i lived in taunton for 15 years, always have had a red daytona of some type mostly 90+

had an 89 z for a while. then two chargers. then a 90 shelby and now a 91 iroc.

maybe we could hook up some time. ill buy you a beer or sumpin.

ill let u check out my swiss import daytona iroc 25 ht. i need a good machinist also i may have some work for you. precision in dighton porked me good. thinkin bout going uo maine to talk to mcmaster next.

cheeers!

[MachIIIRayzor]

When you lengthened your TPS wiring did you switch the wires around to get the correct signal?
The TPS sensor on the Caravan TB I used spins the opposite direction so I had to reverse the wires to get the proper TPS signal voltage.

You can also try out a stock SMEC just to rule out that possibility.

Also the distributor being driven off the cam spins couter clock wise instead of clock wise, does the Hep wiring need to be modified to correct for this?

[turbopac]

taunton fellas I live right near ya I'm in R.I. lets hook up have some beers and check out the iron I dont see many TDs around

[jonnymopar]

Quote:

Originally Posted by MachIIIRayzor When you lengthened your TPS wiring did you switch the wires around to get the correct signal? The TPS sensor on the Caravan TB I used spins the opposite direction so I had to reverse the wires to get the proper TPS signal voltage. You can also try out a stock SMEC just to rule out that possibility. Also the distributor being driven off the cam spins couter clock wise instead of clock wise, does the Hep wiring need to be modified to correct for this?

I never heard of having to switch the wires. Hmm, that would be something to check. I have a stock 89 SMEC in it now as a diagnostic measure. Nothing changed when I switched from my FWD Performance SMEC to the stocker.

The direction of the distributor shouldn't matter because the two hall effect switches are merely on-off switches. So no matter which direction the shutter wheel is travelling, they will still turn on and off in the same fashion.

I still haven't had a chance to check the two outputs of the hall effect pickup. Also, stupid ass me, it dawned on me that I can't check the damn codes because I disconnect the battery when I'm not working on it.

Local guys, yeah, let's set something up sometime. turbopac, where in RI are you?