Custom EFI - Car won't start

So, for the first time in years, my Civic is seeing the light of day. The turbo is "finished" and I went to do an initial startup last night. No dice. It turns over fine, but won't fire. The setup is 450cc injectors running via a baseline boost map in Zdyne. For those not in the Honda know, that is ~90% larger injectors and a fuel table that in theory compensates for the larger injectors with shorter pulse width.

So anyway, no fire and I'm trying to figure out why. I checked for spark and it is healthy. I've got fuel pressure (though to be fair I haven't confirmed fuel flow). As a diagnostic tool I tried starter spray, on the theory that if there is a fuel problem, then it will fire on the starter spray. No dice. That led me to believe that rather than too little fuel, I may have too much. Would these be the symptoms from flooding the engine?

I'm not a Honduh person, but, motors is motors.

Pull the plugs. Are they wet with fuel? Way too much, but you know that there is fuel going in. You say there is spark, but is it in time? If this is a new computer control system, it may not be set to recognize whatever your pickup is, or delaying the timing differently than the OEM unit. Timing light.

I have some hints here: http://www.drhess.net/Clip_n_Saves.htm#Cranks%20but%20won't%20start

I'm betting on timing.

Timing should be fine, as the car ran when parked, and it hasn't changed.

It's not a new computer, just custom maps in an OE computer, so sensors should be talking OK.

If you suspect way too rich, pull the injector harness and then try the starting fluid again. If you have good spark and timing, I'd think that would at least give you a stumble. What does the exhaust pipe smell like? Any chance the injectors aren't atomizing properly?

Is there a Natty light can in the air intake?

By "spark is healthy" have you actually verified that your coil is getting signal from the module at the proper time?

John Brown wrote: Is there a Natty light can in the air intake? By "spark is healthy" have you actually verified that your coil is getting signal from the module at the proper time?

"Spark is healthy" means that a plug grounded against the block made a decent spark. I haven't confirmed timing, other than knowing it hasn't changed since the car last ran.

Crash wrote: If you suspect way too rich, pull the injector harness and then try the starting fluid again.

Good thought.

Any chance the chip may have changed the cranking timing too much? Wouldn't hurt to check with a timing light.

Dr. Hess wrote: I'm betting on timing.

I was thinking that just before I read it!

Even the most horrendously off-mixture engine should give a little sputter when you try to start it. If it's not the timing then it's definitely not getting fuel.

Why not pull a spark plug and give it a crank and see if fuel sprays out the spark plug hole? Extinguisher ready and people out of the danger area of course

MadScientistMatt wrote: Any chance the chip may have changed the cranking timing too much? Wouldn't hurt to check with a timing light.

The spark map is identical to OE, but with boost retard.

Reading a timing light at cranking RPM is somewhere between rediculous and impossible. I tried last night.

I've never had a problem reading a timing light at cranking RPM. I think you are honing in on your problem there. Put some liquid paper on the timing mark on the pulley and another dab at wherever it is supposed to be on the block.

DILYSI Dave wrote: The spark map is identical to OE, but with boost retard.

Hey now, there's no need for name calling!!! Like Hess said, I've never had a problem using a timing light at cranking speed. If spraying starting fluid isn't even getting a sputter, you're either pig rich (disconnect injector plugs and pull fuel pump fuse, try starting fluid after clearing it out) or something with spark isn't right. If you've got strong spark (that will jump a good gap) then it must be timing.

Good luck, let us know what you figure out. I still wouldn't trust a custom chip much, if you have a stock ECM/chip, I'd stick it back in for grins.

Bryce

I am so glad that I am not the only one who uses "pig rich".

I believe the tach should respond when you are cranking it over; if so that along with the spark should confirm that the ignition side of things is okay.

Tried a noid light to verify injector pulse yet? If you have no pulse or if the noid stays lit all the time, swap another ECU and give that a shot.

A blocked intake is not completely out of the realm of possibility. I have seen mouse/rat/squirrel/mud dobber nests all over cars that have sat for a while. Worth a look.

Also, check the TPS; on many engines if the TPS is over a certain value during crank the engine won't start because the ECU thinks you are holding the throttle to the floor.

John Brown wrote: I am so glad that I am not the only one who uses "pig rich".

Farm animals never do anything right....

Jensenman wrote: A blocked intake is not completely out of the realm of possibility. I have seen mouse/rat/squirrel/mud dobber nests all over cars that have sat for a while. Worth a look.

I did get a dirt dobber nest in an exhaust port since it sat without a header for a while. The intake OTOH was always protected.

Are you sure you have the correct resistance injectors in it? - Peak 'n Hold vs Saturated? If you don't, the ECU may not be capable of opening the injectors if you still have the factory resistor box and added high resistance injectors to it.

Have or can you try putting a stock ECU in to see if it will fire. I doubt that even doubling the injector size would make it so rich that it wouldn't even sputter a little at the stock startup pulsewidths. You have to get WAY off to get a solid no-start. That said, it should easily start with injectors disconnected and starter fluid. If you can't get any action from that, then it sounds more like spark timing is wrong - maybe the ECU is expecting a different reference angle from the distributer or a TPS signal that rises instead of falls or something like that? You should be able to read timing at startup rpm and verify that it is somwhere around zero +-20deg.

-Chris

2 plus year old gas might have something to do with your problem.

Your Injectors are too big to start. If you can get it running stock then start with the mods.

clownkiller wrote: 2 plus year old gas might have something to do with your problem.

Gas tank was emptied and dropped for the Walbro 255 install. New 100 Octane was put in, and the system has been flushed .

GVX19 wrote: Your Injectors are too big to start. If you can get it running stock then start with the mods.

How do you figure? Stock injectors are 240cc, and don't have a lot of overhead. DSM 450's are a common swap in turbochartged Civics because they are physically the same size, use the same resistor box, and plug into the stock plugs.

I did find that the startup fuel enrichment was 255%. Lowered that down to 120%.

"For those not in the Honda know, that is ~90% larger injectors"

If you do not have the eng running and you dont know why. 90% more fuel on start is a good place to start.

Do you have the any feed back from you ECM? Air temp,map,coolent temp,rpm? If so what are they when your cranking?

Here's what sorta bugs me: if it's got spark, then spraying ether or whatever in the intake should make it pop or something, if the timing is way off most likely it will blow flames out of the intake or exhaust and scare the crap out of you. No flames or pop = either no spark or the fuel is not getting sucked into the motor.

Do you have vacuum? Check it the old fashioned way, stick your hand over the air intake and spin it over. No vacuum = something's plugged. Caution: if it does decide to fire and a valve's hanging open, your hand could get cooked pretty quick.

Valves stuck open? Over the years, we have seen lots of engines with valves stuck due to fuel residue deposits on the valve stems.

Pulled Fuel rail assembly out of the intake. Injectors appear to pulse properly. Spark is sparking, but I still can't tell if it's at the right time. Decide to replace parts to see if there's a problem. Replace cap, rotor, and wires. Plugs are new. Still nothing. Replace ECU with stock. Checked starter fluid / no fuel scenario with stock ECU. Still nothing. Berkeley.

I'm getting no error codes from the ECU, but it generally won't throw codes during startup unless it's for something like an unplugged sensor.

I do have vacuum. Still, the stuck valve thing is interesting. I have been under the assumption that compression is a given, but it looks like a compression test is in order just to confirm.

I feel like there has got to be something that is retardedly simple that's berkeleying with me. I swear I don't know what though. I don't have a spare dizzy, or I'd try that next. Grrr...

Oh yeah - checked distributor fully advanced, fully retarded, and in the middle. No change.

I think it's got to be an ignition issue.

Tonights tasks:

• Confirm Cam and Crank are timed together.
• Confirm good compression
• Install replacement distributor (which houses all pickup and ignition components)

Anything else?