power loss at high revs
 

Hi everyone,
Can someone help me out with this problem before i give my car to mazda and end up spending a fortune on things that dont need doing.

Seem to have this issue this weekend, driving on the motorway, i shift from 3rd to 4th gear i get past 5k and the enging sounds like its struggling and i loose a bit of power, at the moment it only happens in 4th and 5th gear at high revs, it seems fine around town dont seem to have any power loss around town, coils and plugs were changed anout 12k ago so hoping its not them, if it was wouldnt it loose power alot of the time not jst when im cruising on the motorway? I need to take it to mazda but the first thing they want to do is compression test, any thoughts from anyone? Thanks

That could be a clogged cat.
Have you had a CEL?

No cell,
Just spoke to a rotary mechanic and he said it could be oil on the maf sensor because i may of overfilled the oil on friday then took it on the motorway for a good run he said if it was the cat it would do it all the time

That could be it, but when mine went bad it started at high rpm, but I did get a CEL for a bad cat first.

I just took the airbox and filter, theres no oil in there i also took the sensor off, its not covered in oil but its a bit oily so not sure weather to just clean it with some cleaner or just replace it, the car dosnt loose any power until im cruising in motorway in 4th and 5th gear but not major but defo some loss of power and engine sounds different but around town i can still redline from 1st to second and 3rd, very strange

Clean the ESS and MAF sensor with some MAF cleaner see if that helps.
If you haven't had a CEL, I don't think that's it, but it wouldn't hurt to check it.
No problems with hot starts?
Dying fuel pump would be my next guess.

Yeah you need to diagnose the issue properly. With no CEL it is likely not a misfire but a deep scan wouldn't hurt, you can get misfires without a CEL. It could definitely be a fuel pump issue.

Engine ---> Sympton Troubleshooting -----> NO.12 LACK/LOSS OF POWER-ACCELERATION/CRUISE
M A Z D A

How will i know if its the fuel pump? Shall i just change it and see what happens, or will mazda be able to tell me on a diagnostic cpu, sorry might sound like silly questions i just know what these dealers are like i know what will happen, as soon as i give it to mazda i will end up paying out £££££s just to check everything, when it could be something simple

You need a gauge, you don't have to go to the dealer, if you know of a reputable mechanic shop, they might be able to do it.

Well if you want to diagnose by parts replacement feel free. But it might end up costing you even more money in the end.

Yeah dont want to start replacing parts if they dont need it, my local garage is doing an mot and a oil change tommorow so ill ask them to check the fuel pump.

I assume you have checked all the obvious stuff like making sure nothing is unplugged (vacuum hose, electrical), the spark plug wires are secure, etc?

I havnt actually checked the plugs but if they were loose there probs would be power problems from the moment i drive the car, now im back to city driving the car is perfect i can floor it to redline no problems or power loss, it just when i get on the motorway in 4th and 5th gear as it goes over 5k revs, its very wierd its not even that major but i can 100% feel that power lag.

My car had its mot today, it went through no problems, emission test was bang on but the garage wont look into my problem as he wont touch rotary engine, wouldnt even check the fuel pump, where is the ess sensor? Ill clean the maf aswell may even drop in another filter then still see if i have the problem occurs.