Well I spent some time searching for noisey throttle body's and all I could find was that they do make noise. That's it, no videos or anything like that. I live in Wisconsin

 

Never heard one quite that loud.

Maybe PM Williard and see if he has a spare you can try. I'm in Canada just north of Seattle so kinda a long way to ship for a test 😊

 

Well I appreciate that and I'll give him a holler. Do you really think this issue could be as simple as that?

 

it could be. I'm. Surprised it isn't throwing a code....but sometimes this car Surprises me

I've seen a few that wouldn't idle for crap and it turned out to be the throttle body....and no CEL...so there is hope 😊

 

Not so sure myself. Didn't seem that abnormal to me and I'd expect other driveability issues. Basically it's just the DBW and TP sensor hardware housed in there. I can't be sure though so swapping a known good one on there would confirm it right away.

 

I'll look into seeing if I can get one to try. The only thing that is picking my brain is the 1 misfire I had when I drove the car a few miles after looking over everything and putting it all back together. You guys know more than me but I wouldn't think my TB (faulty or not) would cause a random misfire.

 

Lots if things can cause a 1 time misfire. ...even the reset. If it is a one time thing not much of an issue.

if it was misfiring all the time then I would worry more about it

 

Agreed

 

don't know if this helps, does this have something to do with the the ssv?

get well soon!

 

All intake valves are in working order from the solenoids/ motor to the valves themselves.

I'm going to check the fuel pump resistor just for fun when I get a better multimeter.

I just took the car for a little cruise and I noticed that with light/half throttle I was able to rev to 7-8k without any issue (didn't try to go any higher). Also, that when I was cruising at 6-6.5k under light throttle, whenever I put the pedal down it would almost instantly go back to the weird rev limit problem. So it's starting to seem that whenever I start to get on it is when the problem arises.

I have a new throttle body coming on Friday hopefully. I got a good deal on a new OEM one and I'm hoping at the least, it'll be quieter than the one I have.

Thanks for the help guys.

 

take the intake off and I think you will find it actually is normal .


Just reading through the thread .
You did mention a misfire so I would definitely check the coils with an hei tester per Teams' coil test thread . Those D585s are often faulty from the get go.
Also I would take a log at full throttle and record the AFRs as it reaches the limit . You say 13-14 earlier which is way leaner than stock at full throttle so that isn't normal.

 

I have a shitty reader but I'll see what I can get for a better answer on the afr. Within the next 2 hours or so

 

I drove home and realized that I forgot my OBD reader, do I didn't get any data on AFRs. I did however find out after a lot of speeding, that it happens AT ANY RPM whenever I give it more than 85-90% throttle. Anything less than that, it drives just fine at any rpm.

I'm going to check the coilsin a little bit here.

 

Well that's a bit better information ......... so hard trying to guess a problem when the description given isn't even correct .

Coils or fuel pump would be my best guess from that info .

 

I understand that and I do feel stupid for not noticing it before. I guess I usually always ramp in more throttle as rpms go up and I must do it pretty damn consistent haha. Plus just the fear of causing even more damage made me not want to push the boundaries of where the issue would occur at

 

So I just checked the coils/wires and the plugs are 20 miles old. Everything checked out good.

As far as the fuel pump resistor goes, let's just say it's bad. Wouldn't that make the pump only run in high speed mode? Meaning that couldn't be the issue? I'm still trying to get a good multimeter that will accurately measure that low. Mine will only show .3

As far as the pump itself, it's an S2 unit that is not very old. I'll try measuring the pressure tomorrow

 

The easier thing to do is to look at your afrs as they will go leaner and leaner as fuel pressure drops off .

 

If the resistor burns out the pump will stop/not run in low speed mode. If the resistance is too high it will run slower than normal in low speed mode. However, he said the problem is now only happening neat WOT. It should not be in low speed mode then I'd think.

 

So I got some data on the afr when driving.

When I cruise at 3.5-4K just maintaining speed, it stays at 13-14.

When I rev up to 7-8k under light throttle, which causes no problems, it goes down to 11-12.

When I give er the beans, at any rpm, the afr rockets up to 17-19. At that point I experience my issue.

Coolant temp was 176-184.

I know parts do fail, but with the pump being so new, could it possibly be the fuel pump relay? My understanding is that there are 2 realays for the speed. Circuit (low speed) and fuel (high speed). I don't know exactly when the changeover occurs, but maybe the pump just isn't getting kicked into high speed? EDIT: just tested the fuel relay and it checked out

 

easy to check; pull the high speed relay and jumper a short wire between the two fuel pump contacts. It'd be in high speed mode all the time then.


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Otherwise seems like it must either be the fuel pump or the P2/Sec injectors. New pump, so injectors seem more likely. Always better to test and be sure though.

Was it an OE Mazda or aftermarket pump?

 

Okay I'll jumper it and see what happens. As far as the pump, I bought the whole S2 assembly brand new, OEM.

 

The jumper didn't change anything. Relays are good

I've checked damn near everything except the pump itself. I'll do the pressure/leak down test this week. It looks like the new throttle body will be here tomorrow and I hope that is magically it.

 

Like I posted before, it's your pump. Yank it out and put a genuine walbro 250 and while your at it melt the top of the pipe in your assembly down for insurance. I've ran into this problem when my car had the renesis. You floor it and it's like hitting a rev limiter, it just bounces you back. Don't over think it, the pump may be faulty although new.

 

With all due respect checking that to be sure was already mentioned. It needs to be tested first, not just yanked out on an assumption. It would show as a significant fuel pressure drop when AFR goes lean. If that happens then make sure a plastic bag or something didn't get into the tank and block the pump module inlet when you pull it. Also that the pump discharge O-ring is sealed properly (requires disassembling the pump module). The S2 pump module also has a replaceable filter on the pump discharge. It might have become blocked if there was enough small contamination got into the tank somehow; sand, etc.

The S2 pump is different than the S1 pump and it flows almost as good as the 265 LPH aftermarket pumps per my previous link.

That said, I have a new, separate OE S2 pump from where Deatschwerks replaced it with their 265LPH 65C pump when those tests were run. If you find the actual pump itself is bad then I can send it to you to swap out in your S2 pump module.


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