Hoping someone on here knows ACCEL DFI. Other than it's a 454 with ACCEL's Gen 7, I won't get into details unless someone wants to fool with it. I've been working my project for the last year and a half when time allowed and finally ready to turn the key and it won't start. I've checked and re-checked the timing and it's getting fire. I smell no gas even though fuel pressure is 45 psi at the return line on the fuel rail. I've got multimeters and an o'scope but haven't figured out yet how to tell if the injectors are working. With the injectors mounted directly over the intake valves should I smell gas in the intake or would pulling the plugs be a better way to check. They are getting +12vdc at the right location. All the ACCEL paperwork says is to listen for the injectors clicking but with the mini-starter noise that's impossible. Wondering if I scope the ground lead coming from the ECM will I see the injector fire. I'm new to this and don't know much about the ECM or the software except it was supposed to come pre-calibrated for my engine and bust right off. Any help is greatly appreciated.

Thanks,

Scooter

Just lay your fingers on them while someone cranks it. You will feel them. If they are not firing I would look for a crank signal issue.

Just lay your fingers on them while someone cranks it. You will feel them. If they are not firing I would look for a crank signal issue.

agreed, first thing to check is the crank signal. No signal, no injectors firing. Also make sure that you have the config set up correctly for the type of ignition you're running.

Jody

agreed, first thing to check is the crank signal. No signal, no injectors firing. Also make sure that you have the config set up correctly for the type of ignition you're running.

Jody

Thanks guys. I will do that. As far as the config setup I went thru that and believe it to be correct per the ACCEL instructions that came with the GEN 7 and the dual sync distributor. There are a lot of documents (5 or more), they all seem to vary slightly, and reading one in the Plug N' Play software mentioned forcing the timing to 20 degrees which I hadn't seen or tried before. At least I've got everything together finally and now I'm just chasing bugs. Thanks for your input.

Scooter

Thanks guys. I will do that. As far as the config setup I went thru that and believe it to be correct per the ACCEL instructions that came with the GEN 7 and the dual sync distributor. There are a lot of documents (5 or more), they all seem to vary slightly, and reading one in the Plug N' Play software mentioned forcing the timing to 20 degrees which I hadn't seen or tried before. At least I've got everything together finally and now I'm just chasing bugs. Thanks for your input.

Scooter

that whole system is tricky, but that dual sync is real tricky. I actually got rid of mine and went back to an MSD 85551 and bank to bank. Ran great that way.

Glad you made it over here, Scooter. Looking good so far, you got our best tuner and an Accel dealer watching over you, you'll get it figured out. Run the tests and check back often, step by step to the finish.

Distributor 180* off???

I have that system and got it running with no problems. If you don't mind taking the distributor out, you should be able to spin the shaft with the key on and hear the injectors click in rapid succession. Did you go through the yellow/green LED setup with the distributor?

You might also check some of the start-up parameters. I would check to make sure that starting fuel is set at the default (that was a good setting for me) and there is another setting that doesn't bring the spark in until you hit a certain RPM. You want to make sure that is not set too high.

Glad you made it over here, Scooter. Looking good so far, you got our best tuner and an Accel dealer watching over you, you'll get it figured out. Run the tests and check back often, step by step to the finish.

That info honestly makes my day.

Distributor 180* off???

Maybe I didn't mention it before but I pulled the valve cover off to verify the intake valve opened then closed before #1 cylinder started compression stroke, when it hit TDC, the rotor was pointed dead at #1 cylinder. I also checked this when I put the cam in with the timing cover off. If anything, I'm overly cautious about that sort of thing.

I have that system and got it running with no problems. If you don't mind taking the distributor out, you should be able to spin the shaft with the key on and hear the injectors click in rapid succession. Did you go through the yellow/green LED setup with the distributor?

You might also check some of the start-up parameters. I would check to make sure that starting fuel is set at the default (that was a good setting for me) and there is another setting that doesn't bring the spark in until you hit a certain RPM. You want to make sure that is not set too high.

I went thru the blue/red LED setup with mine. It didn't follow the instructions to the letter so I called ACCEL. It won't follow the sequence in the instructions to the letter. I'm doing mine with the dist already iinstalled. With both LEDs on, I rotate the base or bowl of the dist CCW and lose the red LED first, then the blue LED. Called ACCEL and was told this is OK, just keep rotating until the red LED comes back on then goes off and lock it down. Pretty sure I remembered that correctly.

From the Chevelle site, 'put a NOID lite on one of the injectors, put a timing lite on #1, spin it and see what's going on.' I'm thinking any test lite placed on the injector connector will work. This sounds like good advice I couldn't think of yesterday in my frantic state of mind. As far as the parameters, almost positive the startup fuel is at default, at least it looked like the other curves in some of ACCEL's Plug N' Play files. I've checked every screen I have access to but the ECM and the software are definitely going to be weak points for me.

Thanks all for the help.

Scooter

is it popping and spitting and trying to start?

Until the west coast guys wake up, remmeber it's still a motor. If it's getting pretty much any fuel at all, and it's getting a spark at the right time, it must run.

I'm with you thinking fuel. If you had spark but at the wrong time, she'd be popping and spitting and trying to start. you need to verify the injectors are firing, even if it means pulling the distributor out again.

I'm betting that red light / blue light stuff might tie into why Jody went back to batch fire, dunno.

is it popping and spitting and trying to start?

Until the west coast guys wake up, remmeber it's still a motor. If it's getting pretty much any fuel at all, and it's getting a spark at the right time, it must run.

I'm with you thinking fuel. If you had spark but at the wrong time, she'd be popping and spitting and trying to start. you need to verify the injectors are firing, even if it means pulling the distributor out again.

I'm betting that red light / blue light stuff might tie into why Jody went back to batch fire, dunno.

It pops every now and then, very very infrequently, not even every time I try to crank it. I think I may have been in too much of an excited frenzy with some of my earlier posts. Something about this stage of the game turns me into immature teenager all over again. Here's what I've done so far. Verified the injectors are at least clicking. 8 clicks for two revs of the crankshaft or one rev on the distributor. I didn't verify which injectors are clicking at what time. Put a timing lite on it, spun it with remote starter switch, #1 cylinder fires at 20 deg BTDC, which is what the timing tables indicate at low rpm. I verified earlier that the intake valve opens then closes during #1 cylinder intake stroke, is completely closed during #1 cyl compression stroke and that at the end of #1 compression stroke with damper showing 0 deg TDC the rotor just past #1 spark plug terminal. Back up to 30 deg BTDC and the rotor is dead on #1 spark plug terminal. I'm thinking the distributor must be 180 out. I went thru ACCEL's instructions for setting up the distributor again, distributor installed, spinning the base CCW 360 deg. Instructions say you will lose the blue cam LED, then the red crank LED. I lose the red crank LED first, then the blue one, rotate it further to get the red one back on, then a little further to lose the red LED. There is only one location in the full 360 deg rev of the dist where this sequence will happen. Although this does not exactly match the sequence in the instructions, ACCEL tech support says this is right. Thanks for all the help.

Scooter

I'm betting that red light / blue light stuff might tie into why Jody went back to batch fire, dunno.

a local tuner has had a very high defect rate with those distributors, plus I have seen a lot of people not getting them set up correctly. Mine was returned to Accel after I removed it and they said it was bad, but I had already replaced it with the MSD and gone bank to bank. It

The MSD ran so well I just left it in and used the credit from the Accel distributor for some other items.

Jody

I've already pulled my old distributor out of the box, nice GMPP unit with only 5000 miles of use. I'll let this set a while and see if anyone suggests any more ECM/software config things to check before I swap. Can't thank you guys enuf for the inputs.

Scooter

Scooter, can you slam that GM distributor in there, time it, disable sequential fire and spark control with your laptop, and see if this bad boy will run?

you guys have me thinking about the DFI now... All I've ever heard about them before is that:
They're nice.
They're triple my budget.
You need to pay someone to tune them.

And for the most part, other than Jody, the people who have said that have had a nice running megabuck system that they paid someone else to tune.

Sequential is trick. My holley is stone age compared to that...lol.

The entire distributor set up is critical. I like the idea of trying the other distributor, but if should run with the Dual Sync distributor if it is not bad. I have the back door key to Accel, if you do not have it worked out by Weds, I will make "The call" and get you some one on one help with the expert.

I can definitely slam the distributor in and time it. I've got to figure out how to wire it without ACCEL's adapter harness that I don't have since I wasn't going to use this distributor. I've been so intense into this thing I was just going to back off and let my mind rest. I still need to go Christmas shopping. I was on the ACCEL DFI website last night and it stated they're closed until after the 1st, don't know if that was just tech support or the whole ACCEL DFI operation. I'll probably try to decipher the wiring here shortly and try the new distributor after I chew on these config files some more. Assistance from an ACCEL expert via the 'back door' mentioned above would be like finding the Holy Grail. Don't want to sound like their tech support is substandard though. Those guys have always been extremely helpful and knowledgable. Awesome people, awesome forum, awesome site here! Updates when I have them. Thanks.

Scooter

my "expertise" such as it is, is more holley and some factory systems, but if you put that dfi in batchfire, it should only need a tach signal off the neg coil wire.

I'm trying to err on the side of caution here, being far from an expert on ignitions and ECM's. Here's what I've come up with.

I have and MSD 6AL with the MSD adapter harness for GM (part # 8876). Besides Battery power/ground, unused mag pickup, and tach output, there are 4 leads out of this box, red switched +12 and white points trigger both plugged into the factory harness, black to coil negative and orange to coil positive, only connections on the coil.

The GM HEI distributor has a 2-pin connector that is part of the factory harness that plugs into the factory harness side of of 6AL. It also has a 4-pin connector with four ciruits/signals: REFERENCE LO, BYPASS, REFERENCE HI, and EST.

I've attempted to map the ACCEL ignition harness and here's what I've come up with:

ACCEL Pin A: Pink +12V switched to MSD Red +12V switched
ACCEL Pin B: White Timing Bypass to distributor Bypass
ACCEL Pin C: Clear Crank - to distributor REFERENCE LO
ACCEL Pin D: Black Crank + to distributor REFERENCE HI
ACCEL Pin E: Clear Cam - No Connection
ACCEL Pin F: Black Cam + No Connection
ACCEL Pin G: Shield to Ground
ACCEL Pin H: Dark Blue EST/Points to MSD White points trigger

If someone smarter than me confirms or corrects this I'll try it. Otherwise, I'll be more comfortable waiting on assistance/input from ACCEL because I don't want to let the smoke out of anything.

HO HO HO and Merry Christmas!!!

Scooter

Too many wires, that's a computer controlled distributor.
I don't recall how, but there is a way to bypass and lock the timing on that thing. It's used to set the static timing on computer controlled cars using that distributor.

Power to HEI power.
HEI tach to Accel pin H, DFI in batch fire.
And whatever jumper you have to put on that distributor to lock out the timing.

Again, need someone smarter than me to confirm.

If someone renames this thread 'My Dumb@$$ Attack of the Year' I'll understand. After posting the last question about the HEI distributor wiring, I was rummaging around when I happened across my compression gage so, why not check it. No compression. I thought it is mild the other day spinning it by hand but just knew that motor was right. I went for the easiest thing first. I had to readjust every valve. Still not happy with two intakes and one exhaust valve but, after readjustment, the polylocks sit a full 1/8-3/16 taller on the studs. Right now, I feel pretty bad for wasting everyone's time on here, especially being new to this site. I'm afraid I still don't understand. Here is a direct quote from the CompCams instructions I followed to the letter:

"It is not necessary to pre-pump hydraulic lifters full of engine oil prior to installation and valve adjustment. It is actually undesirable to do so as the pumped up lifters will cause the valves to open during the adjustment process, rather than positioning the lifter plunger in its operating position as it is supposed to do."

All I did was wash the new lifters, soak them overnight in a bath of new, clean engine oil before installing, never manually pumped them up. I don't get it.

the truck is running with the dual sync dist and sounds great. It busted right off after adjusting the valves, but what's the deal with the lifters and what are they going to do next. I do apologize for wasting everyone's time.

Thanks,

Scooter

glad you got it figured out. If that's the dumbest thing you ever do you're in good shape! ;) Have a great Holiday, and enjoy your tuning.

As far as lifter adjustment, this method is most preferred by the cam manufacturers and is the only way I adjust mine. I also lift up and down on the end of the rocker where it meets the valve stem to as I slowly turn the adjusting nut down to find zero lash; much more accurate than spinning the pushrod which can give false readings. I'd probably do about 1/2 turn pre-load.

http://www.cranecams.com/?show=techarticle&id=2&PHPSESSID=1c349fcc512428ef36e24a0ef0b5928a

Jody

Way to go, glad you got er lit off!!!

Glad you got it running! I think you hit on a typical situation that many of us have experienced. Be glad that you thought it through before buying a bunch or parts.

I've had no problems with my DFI except for the ones I created. My car runs and starts so good that I haven't been motivated to do the last 10% of the tuning.