1souped7

OK, we ran into a very odd problem today. We were out starting my car for the first time since the engine swap. When starting the car we were able to get it cranking and everything sounded great but we could not get it to do much more then that. We checked and made sure we had spark on all plugs, we checked and made sure we had fuel, and when we took the plugs out and felt we deff had compression. The weird thing is the engine just wouldn't start. We didn't have popping or backfires of any kind, it didn't even feel like the car was trying to turn over much past the starters crank. It almost felt like I was starting the car without any gas at all(but we deff had gas). The car just wouldn't turn all the way over. It was almost as if one of those three key ingredients were missing. My tuner told me that a few months back one of the other rx7's he was dealing with was doing the same thing but the owner ended up changing out the engine harness and the car started right up.

My question to you all is how is this possible? I know there is a certain timing that the car must have to run properly but if my timing was so far off or something was so wrong wouldn't I still be getting popping and back firing? How can I have all three of these in place and not get anything out of the engine? Could there be something not letting it start. Could there be something wrong with the engine harness? What if anything are we doing wrong?


Things we checked:
Fuel is making it to the front fuel lines
The fuel pump is turning on
The spark plug WIRES are getting spark
The firing order/plug placement is correct
The coils are plugged in properly
We pulled the plugs and felt great compression from the plug holes

What could I be doing wrong. It's killing me . Any help would be very much appericiated. Thanks all.

AHarada

iTrader: (25)

It could be flooded. I was in the same situation as you were.

I had my crank sensor plugs in backwards, so my spark and fuel timing were opposite not allowing it to run. I tried it maybe like 4 times before realizing it, and then I flooded it. I couldn't figure it out for the longest time either. I didn't get any kind of popping or backfiring either.

Have you checked for Engine codes? Maybe you have a sensor not responding.

1souped7

When we pulled the plugs they did have a little bit of fuel on them but they were soaked. The ECU is a Apexi Power FC so we were able to override the CEL's.

djseven

iTrader: (56)

Are you sure it was fuel on the injectors, not oil for break in purposes. Had did you test you were getting fuel?? Just having the fuel pump working doesnt mean you are getting fuel.

1souped7

DJseven, We pulled the fuel line from where it meets the hardlines that then go to the injectors. It was for sure coming out. When doing the fuel test we pulled the brand new plugs and smelled them. They deff smelled of fuel and I believe they also had a bit of fuel on them.

Could the timing be so far off it's not allowing anything to happen?
Wouldn't there be some sort of bucking or sound as if the car was trying to turn over? I mean we were getting nothing other then cranking.

Sgtblue

iTrader: (16)

Check the Crank Angle Sensors. I could see them or the pick-up on the pulley possibly being damaged during installation.

djseven

iTrader: (56)

If they are new plugs and you are sure they were definately wet with FUEL then I dont know what to tell you.

1souped7

I mean thats a possibility but how do I know for sure? The Data logit on the Power FC was picking up real time RPM so I think they were alright.

AHarada

iTrader: (25)

How many times did you crank it? If you are in fact getting injection, then it wouldn't take too many times to flood it. I only cranked mine like 4 times and that was enough to flood it. And my plugs weren't soaked with fuel either. The way I cleared out the excess fuel was I pulled the EFI relay, and kept cranking the car with a battery charger on. After a few times, I felt the engine stumble and want to start with the fuel already in the chambers.

If the Crank angle sensors are switched, I'm not sure if you would get an RPM signal or not, but your injection synchronization would be off and it wouldn't start. I believe the correct positions of them are grey on the bottom, and white on the top.

Go over and check to make sure all of your connectors are in the right places. It's easy to mix up the fuel injector connectors.

RotaryBred

unplug your EFI relay and spray a generous amount of starter fluid (about 5 sec. worth) into the brake booster nipple on the manifold. does a hell of a job clearing all of the excess fuel out and should start for a few seconds. at least that would tell u that you have a fuel issue. it works like a charm any time my engine is flooded!

Dudemaaanownsanrx7

iTrader: (23)

mine did the same thing, actually several times, my car kept flooding.

it seemed like the only thing that would help sometimes was buying new plugs, i went through at least 3 sets before i got everything sorted out. I changed to a totally different plug design and got a twin power too, both of those helped alot. But yes if the car floods it wont even attempt to start. no pops no smoke just cranking.
Today i checked all my old plugs which are actually quite new and some of them wouldnt even spark, other ones were sparking way down at the bottom of the plug. i checked about 12 plugs and only 3 fired like they were supposed to, even they were mediocre at best.

If you car is a manual you can try pull starting it. I recommend changing the plugs. were they new? It doesnt take much flooding to ruin plugs it seems.

1souped7

The plugs I had in there are brand new. They aren't fouled at all on the tips and the don't have any sort of blackend tips once so ever.

1souped7

I have a feeling the powder coating I had done on the engine block is causing this problem. I might be way off here but I think the plugs are having trouble grounding out to my engine. Not because the plug holes have podwer coating in them but the grounds currently on my block could be having trouble making connections to my frame. This could be the reason my wires are showing spark but my plugs might not be. Any thoughts on this?

Dudemaaanownsanrx7

iTrader: (23)

You can run some new temp grounds and see

Tom93R1

iTrader: (2)

Sounds more like a sensor problem, if the crank angle sensors are swapped the PFC wont start the engine. If it isnt that I would guess a MAP sensor or TPS signal not making it back to the PFC. Take a look at the sensor check screen in your pfc commander for anything that is highlighted.

There is also a connector on the harness above the ECU where it comes into the car. I think its white? But that one is commonly missed when plugging things in and will also cause similar symptoms.

1souped7

I will give this a shot. I went through hte entire car last night and replaced all the grounds and added new grounds. None of the things I tried helped at all. The strange thing is I know there is spark going to the WIRES, I know there is fuel going to the FUEL LINES and I know there is plenty of compression. What the hell could be my problem. I am jsut so freaking baffled. I am not getting any kind pop or hesitation or even a inking of the engine starting to turn over. It's really wearing on me now.

Dudemaaanownsanrx7

iTrader: (23)

One thing you should know is a rotary doesnt act the same as a piston engine. A piston engine can have all 3 things and will fire/pop/smoke etc, maybe start and die or run like **** until you get things right. A rotary engine needs things more precise especially with a fresh rebuild. compression is lower because the seals havent set, there might not be any oil in the chambers yet to build compression and there is assembly lube that has to burn off. Just because you have spark, gas, and compression doesnt mean you have exactly what you need for it to fire.

I went through the exact same thing when i put my rebuilt engine in. Try some starter fluid see if that will make it pop. And if you have a means of pull starting it do that.

Check each plug by plugging it into the wires and grounding it out make sure you have a nice strong spark.

Try putting a little oil or transfluid in the 2 leading plug holes to build up more compression. Do deflood proceedures just in case.

Buy new plugs. but don't get the stock ones they foul out easy, and the spark isn't as exposed. get the ngk b9egv's they require a special thin socket or turn one down on a lathe. The plugs spark better, don't foul as easy, and are cheaper then stock plugs.

I also got a twin power which helped my starting out too. Check your map sensor voltage make sure its in spec both with a mityvac and atmospheric pressure. Check your cas.

Go48

iTrader: (7)

I assume this is a used engine and not a rebuild/reman. Before you waste any more time, do a proper compression test to verify that you have good compression on all 3 faces of both rotors.

1souped7

It is a rebuilt engine done by a extremely reputable engine building company on this site. We can feel very good compression on both sides so thats not the problem. Other then taking out the plugs and feeling for the huge puffs of air and hearing it making compression what else can I do to test it?

Dudemannn: We are running brand new NGK plugs b9egv all around. Where do I put the starting fluid? How much oil should I put down each one of the intake runners?

1souped7

Anyone else have any ideas or comments?

Dudemaaanownsanrx7

iTrader: (23)

i put the oil in the spark plug holes other wise you would have to wait for the oil to drip down/get sucked into the engine. I take a hose and stick it in a container of oil then plug the end with my hose to hold the oil in stick it in the plug hole and blow in the hose to force it into the chamber. a little squirt can works too. a couple tablespoons of oil should work. there really isnt a set amount just whatever feels right. i usually bump the engine over with the egi out to get it on all surfaces, but dont do it too much or it pushes the oil back out the plug holes.

1souped7

I ended up finding two grounds that were not connected under the UIM. After fixing those and spraying fuel into the throttle body it kicked over. Problem solved. I guess my injectors weren't pulsing due to teh grounds.

Dudemaaanownsanrx7

iTrader: (23)

glad you got it fixed