Car going lean above 4000rpm, DW200 failing already?!
#1
Senior Member
Thread Starter
Join Date: May 2017
Location: Louisville,KY
Posts: 1,132
Total Cats: 97
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Ive had my car together for a year now with no issues. Just yesterday I was driving and went to get on it, it felt like I hit boost cut. I turned the boost down and did another pull watching AFR and the car is going lean above 4000rpm in boost. I went part throttle around 10psi and sure enough once I got to about 4500rpm or so it started going lean again. I let the car cool down and went for another drive and this time it stayed rich until about 5500rpm, once I went to do another pull it got lean sooner, around 4500rpm again.
Setup is a Hydra 2.5 w/ DW200 pump and stock NB regulator, RC550's and a radium rail.
At this point Im thinking its got to be the pump going out, Ive read that a lot of people have had issues with the DW pumps failing on them. I'm gonna do a datalog today to see what the ECU is showing. I didnt touch the tune at all, so its unlikely its tune related. I dont think its ignition related because the car drives smooth, idles well, etc. I can visually see the AFR going lean if I stay in it and of course then the car wants to completely fall on its face when it gets super lean. Has anyone had a DW 65c/200/300 fail on them this early? I went ahead and ordered a Whinebro 255 and a new fuel filter so I will update this once I get the new pump in the car and see whats what.
Setup is a Hydra 2.5 w/ DW200 pump and stock NB regulator, RC550's and a radium rail.
At this point Im thinking its got to be the pump going out, Ive read that a lot of people have had issues with the DW pumps failing on them. I'm gonna do a datalog today to see what the ECU is showing. I didnt touch the tune at all, so its unlikely its tune related. I dont think its ignition related because the car drives smooth, idles well, etc. I can visually see the AFR going lean if I stay in it and of course then the car wants to completely fall on its face when it gets super lean. Has anyone had a DW 65c/200/300 fail on them this early? I went ahead and ordered a Whinebro 255 and a new fuel filter so I will update this once I get the new pump in the car and see whats what.
#3
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
My friend with a 04 WRX had been using a DW for a little bit. It kept failing on him after about 1-2 months. After 3 times of DW warranty replacing or repairing it they finally refunded his money. With all the issues I have heard from other people regarding DW products I wouldn't use them.
Back on topic, to me that sounds like your pump is struggling to supply enough fuel that is being asked for. Could be clogged fuel filter as well.
#4
Senior Member
Thread Starter
Join Date: May 2017
Location: Louisville,KY
Posts: 1,132
Total Cats: 97
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Yea, Im replacing the fuel filter along with the pump. The car was literally perfect for a year and this kind of came out of left field. Ill update this thread when I put the new pump in. If that doesnt fix it then more diag will be necessary.
#6
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
My money is on the fuel filter, and then the pump.
#7
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
It's not the AFR sensor. He already stated that the car falls flat on its face when he gets into boost. If it was just a measurement problem, the car would still work.I'm going to assume that despite how shitty Hydra is, it doesn't allow for any sort of wideband-based fueling correction under real load.
My money is on the fuel filter, and then the pump.
My money is on the fuel filter, and then the pump.
#8
Moderator
![](/mt2011/images_td/ranks/supporter1.gif)
![](/mt2011/images_td/ranks/moderator.png)
iTrader: (12)
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 20,885
Total Cats: 3,075
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
You said it's felt like Boost cut. Fuel pumps don't feel like a boost cut when they fail. The boost cut stutters. Description sounds like ignition, including going lean. Could be either though.
My DW is a 2012-ish and is still going.
My DW is a 2012-ish and is still going.
#10
Moderator
![](/mt2011/images_td/ranks/supporter1.gif)
![](/mt2011/images_td/ranks/moderator.png)
iTrader: (12)
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 20,885
Total Cats: 3,075
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I don't know if there is, other than going lean and stuttering in boost. Try gapping the plugs down slightly and see if it moves the problem up the boost gauge any.
What coils are you using?
What coils are you using?
#11
Senior Member
Thread Starter
Join Date: May 2017
Location: Louisville,KY
Posts: 1,132
Total Cats: 97
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
It's not the AFR sensor. He already stated that the car falls flat on its face when he gets into boost. If it was just a measurement problem, the car would still work.I'm going to assume that despite how shitty Hydra is, it doesn't allow for any sort of wideband-based fueling correction under real load.
My money is on the fuel filter, and then the pump.
My money is on the fuel filter, and then the pump.
Walbro will be here tomorrow along with an OEM filter so I will know soon enough.
#12
Senior Member
Thread Starter
Join Date: May 2017
Location: Louisville,KY
Posts: 1,132
Total Cats: 97
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Well I was driving my favorite back roads and went to hit it in 4th and noticed the exhaust note was choppy. Like it was pulling but it was unhappy. Checked the AFR and noticed it going lean under boost. Turned the boost down and did another pull and this time it went super lean and that time it felt like boost cut because it went so lean 16 + AFR that the engine felt like it hit fuel cut. Coils are still the stock NB coils which I realize are known to suck and go bad. The reason why I think its not the ignition is I can go part throttle on the highway, say 5th gear....from 3500 and then watch the AFR just start to slowly lean out as the RPM rises.
#13
Senior Member
Thread Starter
Join Date: May 2017
Location: Louisville,KY
Posts: 1,132
Total Cats: 97
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Plugs are gapped down already @ .022. Yes before the car totally fell on its face the car was still pulling but stuttering as you describe it. The next pull I did it went much more lean and thats when it totally hated life and cut out. I think the pump is failing at an alarmingly fast rate. I really hope its the pump and not something else I have to diag....lol
#18
Senior Member
Thread Starter
Join Date: May 2017
Location: Louisville,KY
Posts: 1,132
Total Cats: 97
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Verdict : the dw200 is a POS. Dropped in the walbro and it's back to running like a good girl. Thew in a new filter too, but the old one was not clogged at all. So honestly I can not recommend a dw pump. I've never had a pump fail so quickly. It is more quiet than the walbro but that's about the old good thing I can say about it.
#19
Senior Member
Thread Starter
Join Date: May 2017
Location: Louisville,KY
Posts: 1,132
Total Cats: 97
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Duty cycle is the same with the Walbro vs the DW200 so the pumps ( when working ) appear to supply the same amount of fuel to the engine. I loved how quiet the DW200 was and it was doing great up until it wasnt. I feel bad because I told two friends ( one going 2554R and the other going mp62 ) to get the DW200 and they already have the pumps and are installing them. I hope they have better luck than I did.
#20
Retired Mech Design Engr
![](/mt2011/images_td/ranks/supporter1.gif)
iTrader: (3)
Join Date: Jan 2013
Location: Seneca, SC
Posts: 5,011
Total Cats: 859
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
My DW100 did not last long at all. The DW200 takes a long time to prime, but otherwise works fine. About 1 year of use so far. Return style conversion.
Re: duty cycles (presuming you mean injector DC), that is more your FPR than pump, unless you make an extreme change in pump size.
Re: duty cycles (presuming you mean injector DC), that is more your FPR than pump, unless you make an extreme change in pump size.