TheWoganSleeve

MY air temp sensore is reading crazy random digits on the apexi hand controller,
1, where is i
2, how do i fix it

Also i got my AFR readings and power yesterday at WGT its 330.40 bhp (great) but its running so lean its about to blow up , he said.

So i need a remap, hmmmmmmmmm, will the Air temp sensor replacement improve the air fuel ratio.????

Please help ive looked on the search but the results it returns seem to be off topic

Nighrider32

Well a Power FC could help you set your air to fuel ratio so your not running it to lean. but im not sure if that would be the only thing you could look into. anyway heres the link to that part http://www.rx7store.net/SearchResult...x=0&Search.y=0 and hey good luck with your FD.

Mahjik

iTrader: (1)

He already has a PowerFC:


TheWoganSleeve,

The Air Temp sensor is located on the bottom of the UIM. Unless you have a lot of stuff removed from your UIM and some small hands, you'll most likely need to remove the UIM and flip it over to get to it.

No.

Sgtblue

iTrader: (16)

I don't understand. When my IAT went bad, it ran VERY rich...????

Tim Benton

iTrader: (1)

I wouldn't say no, but rather, with a AT sensor working in it proper operating range, you'll be able to trust the data it's giving you. The ecu does use it to control fuel based on air intake temp but it's a very slow moving sensor. If it's way out of range and not just the PFC screwing up, then it probably isn't making the proper fuel corrections with regards to the air temp it thinks its seeing and what it really is seeing.

Make sure the sensor is bad and replace it, one less variable you'll have to worry about when tuning.

Tim

Mahjik

iTrader: (1)

Yes, but he is saying he is running lean. If he's running lean, the IAT most likely isn't causing that. It may be causing (as already stated) improper corrections to be made for tuning, but the IAT itself won't fix his lean condition. Tuning needs to happen.

When the IAT fails on a stock ECU, the ECU goes into a limp type mode (which is rich and runs like crap).

Sgtblue

iTrader: (16)

Ahhh, I missed the "running lean" part. Sorry if it sidetracked.

sdminus

TBH I cant see he would be on the verge of a blow up. I cant see that pip will have altered the air temp correction factor from stock. there is going to be a 20 % differance from min to max if that much.

You may want to replace the IAT into a better location and also with a faster response model. There is a thread on MRC about it

Scott

TheWoganSleeve

Thanks, so i take it a remap is the answer??

pip said i should change my fuel filter, this car was supposed to have been remapped at hayward rotary but aparrently they dont have a dyno (mis sold)

Heres my readouts, i have non sequential cheap conversion apparently so the turbo pressure is crap, take a butchers and tell me what you think,

can the apexi sort it?

Is my RX gonna blow? ive already done 2000miles in it on this map at least and been ragging it. cheers all

Tim Benton

iTrader: (1)

From 6K up, your over 12 to 1 and leaner - yeah, your playing with a time bomb. Add some fuel up there, change the fuel filter if you can't determine how long it's been to be safe.

Tim

TheWoganSleeve

ah so is it just after 6k i need to richen it up? I was shown a graph of how it should look and the whole thing was an inch or two lower on the graph.

Can it be done simply with the hand held?? or can it be altered to be lean easily with that? It was remmapped but 5 months ago so i dont understand why its like this.

twokrx7

iTrader: (1)

Replace that air temp sensor now, if it's reporting flacky temps that POS can ruin your day. I hope it not a wire issue as the sensor usually fails and reports low temps so you run rich assuming you have enough fuel pump and injector.

I suspect your fuel pressure is dropping at high rpm, rewire the fuel pump and recheck AFRs. Then verify that you are not maxing out the injectors.

TheWoganSleeve

I still dont know where it is (UIM)??? what does that mean
POS also not sure what that means,

ill replace sensor and fuel filter and see what happens, but for now ill be driving it slowly if at all

Mahjik

iTrader: (1)

UIM = Upper Intake Manifold

That is the piece that the throttle body connects which brings the air to the Lower Intake Manifold (LIM) and eventually into the core block. The UIM is the part that begins the Intake Runners (i.e. separating the air path into 4 smaller channels of air).

Mahjik

iTrader: (1)

Check the picture, I circled the UIM for you.

Sgtblue

iTrader: (16)

POS= Piece Of ****

NissanConvert

iTrader: (1)

I might be the only one that noticed this but 330whp? are you still on the stock fueling system? If so you're pretty much maxing out your injector duties. That said you won't see your high injector duties on high speed runs but on your 0-?? sprints usually in 1st or 2nd gear.

Add that to your lean a/f ratios and you don't have much tunability to improve your afrs. time to tone the power down a bit?

http://maxcooper.com/rx7/how-to/fuel_system/calcs.html

TheWoganSleeve

Still on stock fuelling but that figure is at the fly, its 291 at the wheels, do i still need to down tune? and will this improve my afr? can i turn the boost down a little?

GregFD3S

a bad air sensor would make it run rich, not lean.

you can adjust your ignition map from your hand controller to correct (+ or -) your base map that is installed on the PowerFC unit. you can do this by selecting settings, select inj map, then adjust the fuel ratio correction. when the adjusted value gets higher, the fuel mixture gets richer.

ideal mixture is 14.57

for example, the fuel correction value is if the air fuel ratio is 12.0, then the corrected value
would be 14.57 divided by 12.0 = 1.214.

you change the values by selecting the range RPM and Absolute Pressure desired, press next twice, then change the current number (should be 1.00 or something) to the corrected value, which is 1.214

that will change your fuel mixture for the selected area. if you dont know what im talking about, i would suggest you have a professional do it for you.

NissanConvert

iTrader: (1)

I'd recommend doing all of the above to solve your fueling issues. Turn down the boost to at most 13lbs. Work on fuel delivery before you turn the boost back up.

The calculations site that i mentioned above can also help you determine what you need as far as fueling is concerned- at the bottom of the page there's a section for boost vs. lph for your fuel pump.

Denso supra pumps are cheep.

BoostedTimmy

If your going to remove the UIM yourself
http://www.clubrx.org/default.asp?id...ntent=63&mnu=5
An excellent guide by Dale

TheWoganSleeve

Thanks for all your help guys, i still have more questions though, where is this sensor? exactly and what does it look like?

Im still a bit frustrated as my car has been ragged all over the country with no probs and now after the power run, the car runs differently, the engine feels/sounds different, like somethings been changed and now the knock sensor is on alot more than it used to be.

Im not happy really, my car was bought remapped about 4 months ago and now Pip wants 200 quid to remap the pfc and i dont have the handheld and now its lean and its about to blow. so im not driving it.

Should it really cost 200 quid then vat to put this right?
He did mess with the PFC for 5 mins B4 he did the power run, i think he may have accidentaly leaned my mixture out? Cos it does feel different,

What should i do about this?

I will fit a new sensor when i find one and a fuel pump as a precaution but i dont want to spend all that cash on a remap when you can just plug the pfc in and sort it in 5 mins?

Thanks everyone

TheWoganSleeve

The pfc air temp readings where changing about 5/10 times a second ranging from -30 to 30+ flickering rapidly btw

Mahjik

iTrader: (1)

It's the ONLY sensor screwed into the bottom of the UIM.

TheWoganSleeve

so the ideal mixture is 14.57 parts air to one part petrol across the whole rev range??? looks like ill be getting a 'proffesional' to do it