Please diagnose! Still having problems 9/7/2012
 

Hi guys just a quick Q after searching and trolling through many many threads....

I have power loss after 4250rpm, It will go up all the way just really really slowly, Only under load if i'm stationary its fine. Under load the exhaust sounds muffled, doesn't backfire and NO CEL? This all started after fitting a new fuel pump, A BHR Off of ebay.co.uk fitted it no problewm,melted pop off cap fine.
First time starting she was a little rough to get going.. The next time i started her she took 5-8 seconds to fire up,here's the weird bit...If i start stop, say drive across the road to the garage to get fuel and turn it off before its warmed,when i start her up after she fires up first turn literally instantly!
So onto my question.... Could the NEW fuel pump be kind of starving the engine? Causing loss of power at and after 4k rpm? I knowp it could be the cat but i have an MOT tomorrow and don't really want to A) Gut the CAT Before MOT or B) Ask the friend at the garage (who i haven't seen in a while) to plug another car in for the emissions. PLEASE HELP ME MY FRIENDS ACROSS THE POND Xx

Without measuring the fuel pressure it is hard to say. The symptoms could be the cat or ignition related but if you don't have a CEL then that is strange. Have you double checked the obvious stuff to make sure no vacuum lines are disconnected or there are no missing clamps, etc.?

I'm assuming you replaced the fuel pump because the last one failed. When mine failed it took the cat with it causing similar symptoms. Could also be something simple like a kink in a fuel line from the pump install.

Clogged catalytic converter.

Thanks guys i just needed to hear it really lol i thought it would be :-( Had a faulty coil when i got her,idiot garage the previous owner took it to only changed plugs! I changed plugs,leads and coils when i got it. Reckoned the cat may have fried then.
Changed the fuel pump as she wouldnt run on less than a tank! Got annoyed coming back from Japfest when i raced a starlet then got passed by him 10 miles down the road where i had broken down :wallbash: She's off to the garage tomorrow for an MOT so ill take it from there, think i may just get a 200cell CAT replacement as its cheaper and apparently better? Ill keep this thread updated then delete when resolved. Thanks again!

Right so my car went for MOT today...Passed emissions first time! Failed on front brake balance though. Bonus now is im off to the garage in the morning to take the cat off and see whats going on :-) Also to take the front pads off and sand them slightly to remove any glaze, failing that ill get my fat bastard maate to sit on the otherside when the even fatter bastard mot tester is doing it.
The garage have said it could be doing what it is due to the new pump over fueling?
That could be spot on as deisconnection the fuel pump fuse when its running then replacing and starting the car makes it start first turn?!? It doesnt normally but starts better warm.

Im waiting for Mazda to ring me back about a PCM flash (mine has had 0,none,nada) Do they charge or is that a free service from mazda?

update Well Mazda / Ford UK fail big time! No response from any of the 6 dealers in my county :'( i've managed to get hold of a pressure gauge for the 8 off a mates scooby. Going to put it on after gutting the cat tomorrow and see how it holds up

Another update....

Took the cat off today (see attatched images) it was FUBAR so we gutted it, Emissions were exactly the same with the gutted cat as with the knackered cat! 0.3 is max allowed and with CAT it was 0.2 without...0.25! Barely passes but its passing!

Was a bit of a mission the guy who mot'd it was there today and he is a cock,they are meant to give each test 3 tries but with him if it fails once thats it. Waited for him to get a phone call then 4 of us took cat off and gutted in under 5 minutes :lol2:

ALOT better power now although still a bit iffy up top revs 1st and 2nd it will go all the way no probs 3rd,4th,5th hesitates. Could it be the fuel pump over fuelling? Im thinking it could be a MAF issue?
Attachment 186386 - Internal view - we laughed and laughed and nearly shat ourselves!
Attachment 186387 - All the ceramic out :-)

its not the fp--checks the coils and plug/wires.
make sure all the intake valves are opening.

Sorry to bump but don't want another pointless thread!

I'm still having troubles here :( plugs are pretty much new but took them out and they were a little oily, Cleaned them up and it was a little better but still has problems.Has new coils ~500 miles ago
Driving hard in first and second is normally ok although in second sometimes she stops at 7k drops to 6500rpm then pops and flies to the limit.3rd gear does the same every time, haven't tried 4th as 8k in 3rd is over 80mph.

Tempted to rip out the SSV but its a long haul and i'm currently participating in Chemo (BOOOO) and don't think i have the energy.

Its a 6port (high power) and reading through the forums says about other valves at higher RPM (APV?) if i were to remove the SSV is it pretty easy to get to the APV? Had a go today but couldn't even get the fecking battery cover out, Seems stuck and is in 2 pieces?!?!

One other thing... If i sit idling 'till shes warm and give the throttle a few blips it sounds muffled? I dont know how to explain it other than covering the exhaust on a nitro R/C Car.

I do love the fire she is spitting but its a bit embarrassing when you go to overtake and the power cuts out :-/ and would love to solve this problem!

One other thing....

Short term fuel trim looks fine goes 0-10 but when she hesitates goes down to -20 this is telling me its fuel related,typically i tried to video it earlier and it ran fine.It did however cost me a £30 on the spot fine for using a mobile while driving :( i kept my old fuel pump,considering swapping it back :/

Take it easy while driving for a while, then check your LTFT's. Over-fuelling will be on the minus side, under on the plus side (along with vacuum leaks). Your real trim at a given time is STFT+LTFT.

Thanks for the reply,ill get some fuel tomorrow and go to Mazda,Pay the £100 they want to plug in and see what PCM flash i'm running as well as a compression test.
Just a note, the UK knows nothing of the MSP-16 flash,mine was last updated 28/1/2008 for "HARD START" TSB 777-01022??

Well went to Mazda got compression test, 7.8 and 7.7 bar.Had it updated but still playing up when less than half a tank :( one thing they did notice was a crack on the top of the fuel pump unit.They seem to think this could be causing the problem?

Quite suprised nobody has any idea! I'm running out of them to be honest lol
Took the ACV/EGR and SSV out today and they were coked up to hell. Also noticed the previous owner must have snapped the radiator nipple off and put a bolt in it instead of replacing it :-/ ive ordered a PC Water cooling 3/8 Barb fitting and will put a thread in the rad and fix it.Only got 7 litres of coolant out of the whole system which worries me somewhat,should have 12 litres in! Could this cause me problems?? Anyways heres a couple of pics of the carbon build up.Didnt take a pic of the ssv but it took me 2 hours to clean!
Imageshack - sam0341d.jpg
Imageshack - sam0339ru.jpg