PinkRacer

I have searched far and wide, but haven't been able to solve this problem yet. It's now been 2 years I've been trying. Perhaps someone can make some new suggestions!

Here are the things that are done to the car so you can see the setup:
- 1988 6-port S4 NA engine - was just built by the previous owner and has never started yet
- Cartech turbo kit with intercooler
- 88 Turbo injectors (550CC) - fully serviced and flow tested before installation
- Adaptronic Standalone S4 turbo 2 PnP ECU with Turbo 2 basemap
- Innovate LC-2 wideband (have calibrated it and connected to ECU)
- AEM adjustable Fuel pressure regulator
- New Walbro 255 fuel pump
- Removed emissions including solenoids/vacuum rack, BAC valve, EGR valve, Air control valve, and air pump. Blocked off or removed all unused vacuum lines

Here are the facts:
- It's getting fuel - lots of it - too much of it. I checked the fuel pressure with my gauge and adjusted it to around 35-38 psi. When we take out the plugs to de-flood, they're wet, saturated actually.
- We re-stabbed the Crank Angle Sensor to ensure the timing was correct, done according to factory spec.
- Checked for spark outside of the engine - there is lots. Arcs very well from the end of the plug to a ground source hooked to the body.
- All plug wires have been triple checked to make sure they're connected to the right plugs.
- All plugs are brand new.
- When you turn it over with no plugs, clear and consistent compression pulses can be heard for all faces. Also, when you turn it over with the plugs in, you can hear the pulses clearly as "thumps".

When we de-flood it, and put some oil in the spark plug holes, then turn it over without the fuel on, then replace everything and try to start it, it kicks a couple times in the way that it would if you were bump starting it - you know when it feels like it's "catching", not the traditional sputter.

Have been unable to ever get this engine to start.

Here is a video of it cranking over:



Any ideas? I have searched and searched, but no luck so far.

satch

iTrader: (1)

Does it start up briefly when using starter fluid? What is the voltage of the Brown/White wire at the TPS or pressure sensor w/key to on as it should read 5 volts.

PinkRacer

Sprayed carb cleaner in the intake (which has usually worked as a starter fluid for me) but it didn't make a difference.

I will check the voltage tonight - on the live gauges on the Adaptronic, the TPS was showing voltage and showing 30% when cranking.

sandy_RE

if its manual have you tried push starting it?? have you had the motor compression tested??

it could be flooded. take your spark plugs out and remove your fuel pump fuse and EGI fuse hold the pedal to the floor and crank the motor for a bit to get rid of the old fuel.
put new spark plugs in put the fuses back in don't pump the pedal just hold it to the floor and she should start.

hope that helps

PinkRacer

We have de-flooded it a number of times fully with all plugs out and EGI out and fuel pump off. Doesn't seem to help. It immediately re-floods when you try to turn it over.

Since it's a brand new engine that has never actually run, its compression is really low. We compression tested last night with a proper compression tester and one rotor was alike 55 psi on all faces, the other closer to 30 psi on all faces.

My understanding is the engine builds compression as it runs/gets broken in, but lack of compression is one of the things that makes a new build hard to start.

The next plan is to roll it down a hill and manually jump start it, but I wanted to cover all other bases first.

satch

iTrader: (1)

That compression is beyond low though.

PinkRacer

Oh, I know.

Next step after all of this is hauling out the engine and taking it apart again (since I wasn't the builder on it) and making sure it's assembled correctly. It has 2 new rotors and a new housing that were used when building it, and a full atkins rebuild kit. I have the receipts from the previous owner.

sandy_RE

yea the compression seems a bit low to start off the key.

hopefully the roll start does the job and you can finally run the motor in.

FührerTüner

iTrader: (5)

Try squirting some atf In there to get the compression up. From the video, the engine sounds like it's turning over too freely, leading me to think the compression is way too low.

PinkRacer

I'm also going to check the injectors to make sure I don't have one stuck open. The injector test on the adaptronic had good results, but you never know.

My other theory was - could a bad engine ground cause the plugs to not fire when they're installed in the engine, but to work when you ground them to an external source?

satch

iTrader: (1)

Not really. One thing you might want to do is pull a plug and rotate the engine by hand via the alternator pulley so you could get a glimpse of the apex seals and see if they are as they should be (as in unstuck and not in pieces and so on).

RotaryEvolution

iTrader: (30)

i say pull start the ******....

RX7s aren't as tempermental but with the RX8s and they flood badly enough it is about the only way to ever get it running again.

i know you did the poor man's compression test and it sounded "okay" but your video sounds like it has extremely low compression, hopefully simply due to flooding. it'll require LOTS of MMO or a pull start to get that engine running to see if the compression comes up.

also, never assume a rebuilt engine is a good engine..

PinkRacer

Yeah the compression test was using the twisted rotors unit, and I agree, super low. Pull start it is!

FührerTüner

iTrader: (5)

PinkRacer

Ok I'm going to de-flood it again, inject some ATF or oil in it, put in fresh plugs, and roll it down a damn hill.

I hate having the engine as an unknown. I assembled the race engine we ran for the last 2 years in the track car, and it ran strong. This one was some guy in a shed who I don't know, however, I have the stack of receipts that show the right parts are in it. That's about it.

There's also a slight wobble in the front pulley, though we rechecked the deflection and it's within spec.

So damn frustrating.

PinkRacer

Tried bump starting, will start when moving then dies when you stop or put the clutch in.

The only way it will run is if it's physically being pulled by our truck on a tow strap and it's in gear. Put the clutch in and it dies. Try to rev it and it won't rev, sounds like some kind of rev limiter/bog when you do it. Will not rev at all, even when being towed. Stop moving and it dies. Put it in neutral and it dies.

RotaryEvolution

iTrader: (30)

got a stock ecu to chuck into it for an attempt? nm, guess that wouldn't work with the odd configuration setup.

personally i dunno, i'd probably just start playing with the CAS, pumping a **** ton of MMO into the engine and using multiple batteries to get the thing cranking as fast as possible while verifying both rotor leading plugs are constantly firing. verifying fuel is a little more tricky and where i usually start with a can of starting fluid.

a compression test never hurts either, to see at least what you are dealing with. if the engine is royally fucked then nothing you do will ever make it wanna run.

PinkRacer

https://youtu.be/Zmy_wb0oCp4

PinkRacer

Yeah, I need to put the air flow sensor back in to run the stock ECU, but I'm going to try it. Had some 20w50 oil in the engine they the leading plug holes and that didn't do the trick. We can't seem to find MMO here in Canada.

Going to try a compression test shortly now that it was "running" a little. And it wouldn't start on starting fluid.

RotaryEvolution

iTrader: (30)

check fuel pressure, verify fuel trims by spraying some starting fluid in the intake and adjust the CAS to see if it attempts to fire off easier.

thewird

iTrader: (8)

New rotors and new housings should have mint compression whether the engine ran or not. Only engines that used poor used parts need to "break in" to get compression and even then if the clearances are tight it shouldn't be hard to start. Unless the engine is drowning in fuel or coolant. Why is the buzzer always on? Have you verified timing is correct on the trailing coil?

thewird

PinkRacer

I suspect there's a bad wire on the coolant level sensor or a bit of air in the system - we drained all the coolant and refilled the whole thing - the buzzer went off for a little while but came back. Seems electrical.

What would be the best way to check the timing on the trailing coil? We have verified that there is spark, that the CAS is in there right, and that the computer has the right ignition timing settings. Since we can't start the car, it's hard to time it using a timing light, though I suppose it can be done while rolling it over.

My working theory is assembly error causing lack of compression on the current engine. We are going to take out the engine, strip it down, drop it in the race car, and throw a carb on it to test it in the most simple application possible (since the race engine needs to come out to be rebuilt anyway).

Failing that, I have a strong running (but high mileage) S5 engine under the bench that is half dressed/half converted to S4 OMP,etc and ready to go in... or...I'm starting to think I should chuck the 6-port bridgeport I have under the bench in it, get bigger injectors, and call it a day. Just need a rebuild kit to freshen it up since it's been sitting for a very long time and to make sure it doesn't have carbon seals in it since it came out of an N/A car and I'll want to run boost.

Going to need a T2 tranny for that though...

RotaryEvolution

iTrader: (30)

can't check trailing timing unless the engine were running, unless adaptronic fires all 4 during crank but i don't know that one.

PinkRacer

That's what I thought - this is where I'm running into problems. You can't calibrate certain things/time it unless it runs, but I can't get it running. Catch 22.

RotaryEvolution

iTrader: (30)

but the leading does fire so you should be able to get an idea if the timing is close based off of that, even though it will be slow and difficult to see while cranking you should still be able to spot the marks.