Tl;dr: Last week with cooling L.A. weather suddenly got:
1. Two cranks on startup are normal, second two sound like the engine is spitting and cranks are a bit slower, 5th crank and the engine starts up as expected.
2. For the first half a minute to minute of driving, there’s a loss of power.

Details: I’m moving from CA to TX in a couple of weeks (driving the 8) and I’m looking for assistance since I have limited time right now to do search function reading.

I have a very early ‘04 model with 83k miles, had reman installed at 52k. Just brought in to dealer 6 weeks ago for a new radiator, t-stat, and the airbag, fuel pump rod and lower control arm recalls. Also asked for zoom zoom decarb, they didn’t know what I was talking about so they called in a salty old mechanic who went off on a rant about Mazda discontinuing that service. They offered their fuel injection cleaning service for an obscene amount of money for what I assume was a cleaner added to fuel, but salty old mechanic said it’s quality for some or other reason and I liked the cut of his job s just went ahead and had it done. Had wires and plugs replaced at 30k even since last swap, but waited on coils since I didn’t want to get up charged on parts and labor, but haven’t yet (few hundred miles later) replaced coils. I installed new red top a couple of months ago.

What’s the most likely culprit? I’m hoping it’s coils or fuel pump, hoping it’s not failing compression. Any other causes I’m overlooking.

Thanks.

 

Is it better when the engine is cold, when it's hot, or same?
What do you mean by loss of power? It won't rev past a certain point? slow to accelerate?

I'd get a compression test regardless, since you're spending money on the car, may as well know what state it's in. Impossible to confirm compression without that. That said this doesn't sound like a compression problem.

 

I’ll check it on a hot start today, but I assume it wouldn’t be present. It’s only noticeable during the first half minute of a cold start. Basically once started cold, it has a loss of power in the lower rpms—like it really hesitates to pick up steam when the accelerator is depressed for a couple of seconds and then it does, but the same thing happens again when shifting to second gear. Then after half a minute of warmup it goes away.

Thanks I will bring it in for compression test, hopefully you’re right that it’s not compression related.

 

How's your coolant level? One thing that could be happening is coolant is seeping through a coolant seal breach and accumulating in the chamber while the car sits. Then when you start, it burns off within the first minute or so.

 

Engine Power Loss
• chokes as revs increase
o O2 sensor failure (too rich)
o MAF failure
o MAF disconnected
o e-shaft sensor fouled
o accessory belt fraying
• high end power loss (hard fuel cut)
o Rev limit reached
• high end power loss (jerky and stumbling)
o Ignition failure
o fuel pressure loss
o e-shaft sensor fouled
• high end power loss (smooth)
o Catalytic converter clog
o air filter clog
• low end power loss (smooth)
o Engine compression loss
• low end power loss (stumbles)
o Ignition failure
o front O2 sensor failure
• revs slowly but smoothly
o O2 sensor failure (too lean)
o catalytic converter clog
o air filter clog
• sudden power drop at a specific rpm
o Intake valving actuation problem
• trouble getting to redline
o Ignition failure
o front O2 sensor failure
o catalytic converter clog
o air filter clog
o e-shaft sensor fouled
o fuel pressure loss
o MAF failure

BTW our RX8club maintenance schedule recommends replacing O2 sensor approaching 90k miles.

 

SPIROGRPAM.....It sounds like we have the same issue. When I cold start the car and start driving, around 5 and 6k RPMs in first and second gear it will sputter real quick and then it seems to grab and continue to climb in RPMs. And this seems to only last a minute or two then I completely goes away. Please post your results of your compression test.

 

Please tell me you're letting the car get up to temperature before trying to rev the engine over 5k RPM...

https://www.rx8club.com/new-member-f...4/#post4533727

 

yes car gets warmed up properly

 

Getting a compression test done today. The tech found a code for a solenoid in the rear of the engine—I’m assuming for the SSV, but I’m waiting on the compression test results before doing any more work.

 

Could be SSV, VDI or SAIP.

 

The solenoid and coils are throwing codes so doing both (coils recently passed 30k). Compression results:

Rotor 1: 7.3, 7.3, 7.1 @ 270 rpm
Rotor 2: 6.7, 6.7, 6.5 @ 274 rpm

 

What code are you getting for the coils?

Borderline on rotor 1 and failing on rotor 2.

 

Not sure on the codes. Think I’ll be able to eek out another 5-10k miles?

 

At least your starter is healthy.

 

Possibly. Compression in my motor has been worse than yours for almost a year now but it depends on a lot of things.

Having the actual codes might help.