Firing the parts cannon to hunt what's wrong with my Suzuki Cara Autozam AZ-1. (Fuel system episode)

trying to figure out why my Suzuki Cara Autozam AZ-1 has a phantom rev limiter at 6000ish rpm
Today info over how to drain the fuel tank to access the fuel pump and float to replace the fuel pump and replace the fuel filter in the AZ-1
#autozam #suzuki #keicar #engine #troubleshooting #fuelpump #suzukicara #autozamaz1 #mazda #mazdaaz1 #f6a #jdm #carmaintenance #pg6sa #pg6ss

[@tbasmwmc]

I'm getting second hand frustration from this😂

[@victorbarra6145]

Check your ignition timing with a timing light, or under the distributor cap is the CMP Sensor (signal generator), check the air-gap and pickup coil resistance, it could have drifted over the years.

[@AnythingWheeled]

I do kinda wanna check timing but access isn't so easy. The crank pulley is buried so it might be a two person job. Gotta find someone to help 😆

[@CappuccinoDrives]

You kid is a smart one. I remember him saying multiple times "Daddy's car is bwoken" while I was there 😆
I hope you at least wiped down the bottom of the tank before putting a new filter...

[@Nick-pl4hx]

I ran into a very similar problem on my autozam a couple months ago, it ended up being wiring gremlins. The pins on fuel pump connector were damaged so the pump was not getting enough power and not spinning fast enough. Replaced the connector and magically everything was fixed!

[@AnythingWheeled]

The blue connector that's in the fuel tank or the one outside?

[@Nick-pl4hx]

@@AnythingWheeled The white one that's on the outside, it should be a 4-pin connector.

[@ultrasupergeek]

I’m in the same boat with my AZ-1 similar gremlin, but mine is struggling to even rev after warming up. Replaced map sensor, plugs ,fuel filter, checked fuel flow. I feel your pain

[@AnythingWheeled]

You figure it out yet or are we still in the same club?

[@tbasmwmc]

That's an ASE certified milk jug.

[@AnythingWheeled]

I just destroyed it by accident. Forgot to close the passenger door and lowered my truck from the lift and it collapsed my drill press table and dropped a big vise onto it 😭

[@drzubik]

W five speed cap, I’m getting ~35mpg without trying. It’s more when I avoid the highway.

[@CappuccinoDrives]

I did hit 50 once on my road trip...

[@AnythingWheeled]

That's about what I get in my Cara. The auto is just less efficient.

[@stephenlmckeown1439]

That are not Philip’s head screws that are JIS which is a completely different driver.

[@AnythingWheeled]

I still call them Phillips, I forget did I use my orange JIS screwdriver?

[@ZUKME]

❤

[@projectmayhemgarage]

Look into the exhaust system. I know that when a cat starts to go, it can cause similar issues

[@AnythingWheeled]

A few people have suggested this now. What would be in the exhaust to cause this? A blockage or leak? I have seen this issue move to different spots between 5500-7500 rpm but it is pretty consistent.

[@projectmayhemgarage]

@AnythingWheeled as the cat starts to get old, it can start to get blocked, and as the cat heats up, the issue will be more noticeable. The Cara will start to feel down on power to.

[@AnythingWheeled]

I don't have a cat. I had a downpipe developed to be catless

[@projectmayhemgarage]

@AnythingWheeled because of the no cat. You may need to talk to the tuner again and have them look over the tune. They should be able to see if all the sensors are working correctly and may be able to see any issues

[@markbaughn1980]

Shouldn't the AZ-1 have an OBD-1 system? Have you tried checking the codes? I know most old JDM cars have a port you can jumper with a paper clip and it should give you a morse type code with the CEL light.

[@AnythingWheeled]

It does, I'm too much of a peabrain to use that. I believe I'd have to pop my N1 ECU back in at this time to see if it'll relog an error.

[@Mightymatt54]

Shot in the dark - Any chance that something's amiss with the speed limiter circuit? For example if the signal from the reed switch is active (like it would be at the max limited speed) due to a short or bad ground, the ECU may be trying to do the speed limiting when the engine hits the minimum limiter RPM (I forget this exact value... it's in the service manual somewhere). That's a remarkably consistent "it stops at this RPM" for a mechanical fuel/air problem.

[@AnythingWheeled]

So I've been stabbing at this more. The N1 and keisport ECU should eliminate this function even though the stock one has that.
It seems to vary sometimes it's 5500 6500 7300 and in the most recent video I tagged just at 9000ish, once.
I have a different theory i want to test but I got sick so it'll wait a couple days.

[@Mightymatt54]

@@AnythingWheeled Get well soon! From your latest video you may be on to something with the fuel pressure regulator. When revving it, it appears that it cuts out around when the manifold pressure goes positive, which if the boost-referenced FPR isn't rising along with the manifold pressure, means you have lost most of the fuel pressure! When testing with that vacuum line off, make sure to plug it so it isn't a leak throwing off your results. Good luck!

[@AnythingWheeled]

@@Mightymatt54 my current testing, I am able to put it into 3rd gear very early and WOT I build and hold full 17psi boost and feel the full thrust like it should until I hit the bad rev range. Does that eliminate the regulator and injectors since everything works? I did plug the line when it was unplugged

[@Mightymatt54]

@@AnythingWheeled Oh, that's very interesting, it would tend to make me look more towards injectors (the rate at which they are actuating rather than duty cycle, since you get full power lower down) rather than the regulator itself. Possibly the higher rail pressure with the reg unplugged under the no-load testing conditions is able to mask a lazy/sticky injector?
Your car owes you an apology after all this!

[@AnythingWheeled]

@@Mightymatt54 I should clarify the regulator bit too I only tested with it unplugged not moving

[@Gravengaard]

Don't reuse the sock on the fuel pump... It's probably crusty and all that. I know mine was. Never mind the size of it, just use the new one. But what a bummer about your problem :-(

[@AnythingWheeled]

I may have to go back in there anyways if I need a bigger pump. I did a Hayabusa pump. I think it's 110 lph but I don't remember. I did wack and blow out the sock so it didn't look bad.

[@Gravengaard]

@@AnythingWheeled I have the SARD 130 l/h for my N2 setup as recommended by Monster Sport 🙂

[@willgreen3665]

Replace the whole distributor....your welcome

[@AnythingWheeled]

Oof if only it was that easy to acquire one 😢 I did find a seller in Japan that sells rebuilt ones for $250 or so but they require a core.