Just as it says. I dont know if the ecu still needs to adjust but i did a third gear pull and a fourth gear pull and it seems that there is less power and it begins to break up above 5 thousand RPM. Few minutes later, first and second gear seemed great. No tuning yet so maybe this is the key factor as to why it doesnt like the extra flow. Any ideas?
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
DP install... breaking up at high Rs
- Thread starter rynzms3
- Start date
Just as it says. I dont know if the ecu still needs to adjust but i did a third gear pull and a fourth gear pull and it seems that there is less power and it begins to break up above 5 thousand RPM. Few minutes later, first and second gear seemed great. No tuning yet so maybe this is the key factor as to why it doesnt like the extra flow. Any ideas?
Sounds like you are getting fuel/load cut. Please search and read threads about fuel cut or load cut.
That is common with installation of a downpipe, especially if you are in cool weather (probably anything below about 60 degrees F., and further especially in combo with your FMIC. I'm assuming you also have some type of aftermarket intake although I did not see that in your sig.
With your extra flow when your ECU determines that you are exceeding the load (maximum power under load) limits set by your stock ECU map, then it abruptly shuts off the injectors, cutting fuel to the engine. It's a safety factor to protect the engine. It typically does not happen in warmer weather (at least on my set up) because warmer air does not carry as much oxygen as cold air.
warmer weather is out for me. Its only march and the hottest it gets in the heart of summer here is about 75 degrees. The past week though it has been about 40-45 degrees during the day but in the mid to lower 20's at night.
The CS FMIC comes with their intake set up so yes, i have an intake. Aswell, they sent me a fuel cut defender that rides under the stock MAP senser. Shouldnt this have solved my load cut problems? I should be able to figure it out when standback gets here this week. With a tune I shouldnt have any worries. For now, i can just drive the RX8 until i get the standback on and tuning. Thanks for the input fellas.
The CS FMIC comes with their intake set up so yes, i have an intake. Aswell, they sent me a fuel cut defender that rides under the stock MAP senser. Shouldnt this have solved my load cut problems? I should be able to figure it out when standback gets here this week. With a tune I shouldnt have any worries. For now, i can just drive the RX8 until i get the standback on and tuning. Thanks for the input fellas.
H3br3w_Ham3r
Member
- :
- 2008 Mazdaspeed3
Sounds like you are getting fuel/load cut. Please search and read threads about fuel cut or load cut.
That is common with installation of a downpipe, especially if you are in cool weather (probably anything below about 60 degrees F., and further especially in combo with your FMIC. I'm assuming you also have some type of aftermarket intake although I did not see that in your sig.
With your extra flow when your ECU determines that you are exceeding the load (maximum power under load) limits set by your stock ECU map, then it abruptly shuts off the injectors, cutting fuel to the engine. It's a safety factor to protect the engine. It typically does not happen in warmer weather (at least on my set up) because warmer air does not carry as much oxygen as cold air.
What kind of noises would be expected with this? I get some loud poping at high RMPs that have come out of no where. I'm not sure if this is the same issue though
Darth Vader
Member
I can virtually guarantee that your high pressure fuel pump is shitting the bed.
Replace those crap pump internals with something that can keep pressure/volume up and you'll be instantly happy.
Replace those crap pump internals with something that can keep pressure/volume up and you'll be instantly happy.
I can virtually guarantee that your high pressure fuel pump is shitting the bed.
Replace those crap pump internals with something that can keep pressure/volume up and you'll be instantly happy.
Really, so when the ECU shuts down the fun again what good will the upgraded fuel pump/internals be?
Darth Vader
Member
The fact you have to ask this amazes me. I'm just going to assume you're not a troll. The car can run to 6K before the ECU starts really getting hyper and reigning in the party. Misfiring and loss of power over 5k with a DP install strongly suggests a fuel supply issue. It's a common problem. Internals should be mod#1 before changing anything on this car.
The fact you have to ask this amazes me. I'm just going to assume you're not a troll. The car can run to 6K before the ECU starts really getting hyper and reigning in the party. Misfiring and loss of power over 5k with a DP install strongly suggests a fuel supply issue. It's a common problem. Internals should be mod#1 before changing anything on this car.
Interesting. My car must have come with an upgraded pump from the factory or the Keebler elves escaped from the drawer I keep them in and installed a pump.
I considered getting a fuel pump recently but decided it was not needed right now. My car seems to have made it 28K miles with a turbo back exhaust, FMIC and no check engine lights or fuel cuts. Heck the car has seen 7k shifts with out giving me any grief. I still don't think everyone needs a pump, I regularly see 1700+ PSI, I get reasonable mileage (depending on my driving style) and no issues.
I am glad that I could amaze you though by not agreeing about the fuel pump.
If your getting fuel / load cut you know it. The car bucks damn hard.
this is definitely not the issue then. I think after a tune i should be fine. Today was better. Its definitely the ECU not knowing what the F to do with the quicker spools and probably a little boost creep.
blh_wakeboard
Member
- :
- 2008 MS3
If your getting fuel / load cut you know it. The car bucks damn hard.
Agreed, haha first time mine did it I thought I blew my motor, I doubt its a fuel pump issue, I'm running 20psi with stock pump and no problems, maybe its a boost or vac leak? just a thought....
Darth Vader
Member
Interesting. My car must have come with an upgraded pump from the factory or the Keebler elves escaped from the drawer I keep them in and installed a pump.
I considered getting a fuel pump recently but decided it was not needed right now. My car seems to have made it 28K miles with a turbo back exhaust, FMIC and no check engine lights or fuel cuts. Heck the car has seen 7k shifts with out giving me any grief. I still don't think everyone needs a pump, I regularly see 1700+ PSI, I get reasonable mileage (depending on my driving style) and no issues.
I am glad that I could amaze you though by not agreeing about the fuel pump.
I'm happy you got a good one. If you look around at how many fail with the addition of a few mods you'd know how lucky you are.
Now I could be wrong here, yes, it could be a bad coil or a worn out set of spark plugs or Keebler Elves in the combustion chamber. Without some form of datalogging or some monitoring of engine parameters, it's shooting in the dark. However, the target painted on the fuel pump ain't exactly small, alot of people have had to fix this issue. If that wasn't the case CP-e and PtP would have got out of the biz long ago.
OP: If it's not bucking by shutting down the injectors and it's acting more like a high speed ignition miss, then pulling and inspecting the plugs is in order, although this could still be be early fuel pump issues.
With both a bigger and higher flowing intercooler and the dp, you may have produced enough power and combustion chamber heat to have burned the plugs, cracking the insulation or to opening up the gap producing a high speed miss.
What plugs are you running, how are the gapped, and how many miles do you have on them? When did you last check them?
With both of the above mentioned mods, you are on the edge of needing one step colder plugs. If you went that route already, you may have fouled one or more of them from low speed driving.
It's cheap (free) to pull those plugs and look at them. If they are clean and there is no evidence of cracked insulation, etc. and they do not have a lot of miles on them, try regapping them, probably down to .028 or even .026 (certainly not more than .030). If they looked burned or overheated or the gap has opened up a lot, then you probably need one step colder. If they are fouled, then go back to stock heat range and gap the new ones properly.
If all looks good with the plugs, then one or more of the coil packs at the end of each plug lead could have started acting up.
Just a thought.
With both a bigger and higher flowing intercooler and the dp, you may have produced enough power and combustion chamber heat to have burned the plugs, cracking the insulation or to opening up the gap producing a high speed miss.
What plugs are you running, how are the gapped, and how many miles do you have on them? When did you last check them?
With both of the above mentioned mods, you are on the edge of needing one step colder plugs. If you went that route already, you may have fouled one or more of them from low speed driving.
It's cheap (free) to pull those plugs and look at them. If they are clean and there is no evidence of cracked insulation, etc. and they do not have a lot of miles on them, try regapping them, probably down to .028 or even .026 (certainly not more than .030). If they looked burned or overheated or the gap has opened up a lot, then you probably need one step colder. If they are fouled, then go back to stock heat range and gap the new ones properly.
If all looks good with the plugs, then one or more of the coil packs at the end of each plug lead could have started acting up.
Just a thought.
Last edited:
OP: If it's not bucking by shutting down the injectors and it's acting more like a high speed ignition miss, then pulling and inspecting the plugs is in order, although this could still be be early fuel pump issues.
With both a bigger and higher flowing intercooler and the dp, you may have produced enough power and combustion chamber heat to have burned the plugs, cracking the insulation or to opening up the gap producing a high speed miss.
What plugs are you running, how are the gapped, and how many miles do you have on them? When did you last check them?
With both of the above mentioned mods, you are on the edge of needing one step colder plugs. If you went that route already, you may have fouled one or more of them from low speed driving.
It's cheap (free) to pull those plugs and look at them. If they are clean and there is no evidence of cracked insulation, etc. and they do not have a lot of miles on them, try regapping them, probably down to .028 or even .026 (certainly not more than .030). If they looked burned or overheated or the gap has opened up a lot, then you probably need one step colder. If they are fouled, then go back to stock heat range and gap the new ones properly.
If all looks good with the plugs, then one or more of the coil packs at the end of each plug lead could have started acting up.
Just a thought.
The car is an 08.5 but there is only 8200 miles it. Close to 8300 now. I believe the issue is with fuel... Here in Anchorage we can only get 90 octane. I think its leaning out in the top end. I have just kept my foot out it until i get my standback in so i can actually see what is going on. Regular driving its fine. Top end of third and fourth gear is where i seem to have problems. Not really sure about fourth gear because i havent done any high seed pulls yet. I dont think I have hit more than 5 grand in fourth. I have never had the car in the triple digit mph range so really were only talking third gear. Im just going to stay safe and wait to "play" until i get my standback in. Thats probably the smart idea. At this point though, i do need to step up to the colder plugs though!
