RX8 cranks but won't fire

I'd look at everything she took apart and put back together, is there a vacuum hose unplugged, or a sensor/wiring harness that got moved and left disconnected? 

How are the batteries in the fob?  We could crank my buddy's RX8, it would fire for a second or two, then die.  Replacing the fob battery to keep the anti-theft happy fixed it. 

In reply to Flynlow :

I looked carefully at everything she did (but I didn't consider the possibility the MAF could be backwards- I'll check that)

Key fob?  I didn't think of that. 
 

Good tips guys. Thank you. 

Next few steps...

- The MAF can't be installed incorrectly. The pigtail is too short. 
 

- We pulled the plugs. They are less than 2 months old.  They were fouled (but not badly).  I'll get some new ones. 
 

- Starter was replaced within the past year.

- I double checked everything she took apart. No loose wires or vacuum lines. 
 

- I don't think the battery is holding a charge well. It was fully charged overnight, but died quickly. Battery is 3 years old. I'm gonna get it checked tomorrow. 
 

- They don't recall the coils being replaced. I get some new ones, and plug wires. 
 

- We are gonna check the fob battery tomorrow. 
 

If it doesn't start easily tomorrow, I'll pull start it. 
 

Yup.... never try to start a rotary if you have a weak battery.  That way lies slow cranking which makes for flooding.

The coil replacement isn't that the old ones go bad, it's that they were bad to begin with.  Lousy spec. There is an updated part from the dealer.

The leading plugs were dry and had very light carbon on them (looked pretty normal).  The trailing plugs were both wet, smelled mildly of gasoline, and minor fouled.

Do these still have one coil for the leading plugs and one for the trailing.  Are both trailing plugs wet?  I bought an 85 with a "bad engine", it had one bad coil and wires crossed from leading and trailing plugs.

Rx8s have  coil for each plug.

L for leading/  lower.

T for trailing / top

There are 4 separate coils. 2 for the leading plugs, and 2 for the trailing plugs. I think all 4 coils are the same. 
 

Both trailing plugs were wet. Both leading plugs were dry. 
 

I don't think the wires can be crossed- it was running fine for weeks before. 

A petite friend had trouble with the airbox, or rather replacing the filter. It looks like an easy job, but apparently requires a bit of arm strength.

In reply to wvumtnbkr :

RX-8 has a coil near plug design on the engine.

j_tso said:

A petite friend had trouble with the airbox, or rather replacing the filter. It looks like an easy job, but apparently requires a bit of arm strength.

In reply to wvumtnbkr :

RX-8 has a coil near plug design on the engine.

Yep, they do.  However, it is still possible to accidentally swap leading and trailing.

I think you'll solve it with the pull start (I've never had luck holding my foot to the floor with the deflood procedure) but did want to give you a heads up, that there are some vacuum lines that run inside and around the air box:



It's called the "VFAD" and it operates before the air filter

As noted, from what I hear, having good coils and replacing the starter with a faster one is supposed to solve the cold flooding issue.

Pull starting, if you can do it, does seem like a reasonable option.

I've had a fresh set of plugs fix a no-start when nothing else seemed to work. 

And I've had the Updated starter lose speed over time on the green car. I bought a new one, started great for 6 months, warranted it and it started great fir 6 months... warranted it.

If the battery is at all suspect, it's unlikely to crank over fast enough to start.

Have you installed the GM LS coils yet?

In reply to chaparral :

GM LS coils?  Tell me more

SV reX said:

In reply to chaparral :

GM LS coils?  Tell me more

For example:

https://www.bennettbuiltperformance.com/products/rx8-ls2-ignition-swap-kit

However, the dwell setting should be adjusted.  This requires a Cobb access port or similar 

In reply to SV reX :

I'm running BHR on mine.  I believe they're similar to the LS units, but either way they've been working great for about 3 or 4 years now.

https://black-halo-racing.myshopify.com/products/ignition-upgrade

Hungary Bill (Forum Supporter) said:

In reply to SV reX :

I'm running BHR on mine.  I believe they're similar to the LS units, but either way they've been working great for about 3 or 4 years now.

https://black-halo-racing.myshopify.com/products/ignition-upgrade

This is the way.

This thing is kicking my butt. 
 

New plugs. New coils. New plug wires. New battery. Turns over fine. No codes. 
 

Still no start. 
 

Won't fire on starting fluid. 
 

Plug removed and held near ground shows spark. 

SV reX said:

Won't fire on starting fluid. 
 

Plug removed and held near ground shows spark. 

Not good.  Fuel air and spark... 

LS swap?

SV reX said:

Won't fire on starting fluid. 
 

Plug removed and held near ground shows spark. 

If it's flooded, starting fluid will only make things worse (I think).  Have you tried the 30mph tug-o-war yet?

Did you crank it for a good 20-30 seconds with the spark plugs out until the white fog stopped coming out of the engine?

Did you add a little oil to the leading plug holes before putting the new plugs in?

If a rotary is flooded these MUST be done to unflood it and build compression again.  Flooding kills compression, it won't start with no compression.

Pull start ... and be patient

I think I mentioned it a time or two ...