Outer Limits 4x4 Board

well.. i'm not sure whats going on here.. i've got several guesses an i'm hoping i can figure it out... i'm suffering from power loss on my roza. i cant figure it out. when i first bought the rig, she could go up a decently steep hill an not have to sift down from 5th into 4th. but gradually i've had to shift down. now its gotten worse! even on level road... i'll drop anywhere from 65-75 down to around 50-55 or so.. then it'll gradually gain its speed back. an this only happens in 5th gear... cant quite figure it out. i'm getting upset cuz i jus had my head rebuilt an a complete tune up. so i have no idea whats wrong. also... my gas mileage has gone to crap. i used to be able to travel atleast 250 miles city an 300 miles freeway driving before i needed to fill up. now.. i'm down to 160-180. its terrible an its pissing me off.
1. o2 sensor?
2. bigger tires doing this? (Doubtful)
3 fuel injection plugged/dirty?
4. intake?
5. air intake??

any info woud be a great help!
also.. if any of u guys know where i can source a factory switch with the factory dash mounts for the rear wiper, that would be great. i need one. my parts truck didnt have it. also, i'm looking for one of the bolts for the rear window.. it holds the window onto the arms which in turns holds the window to the tailgate. again, any info would be great! thx

pv

Could definetly be the bigger tyres...

Also...remember when calculating milage, your spedo and odometer are now out thanks to the bigger tyres so it may not be as bad as all that...

Going from 235s to 31" Tyres, I have to use 4th a fair bit on good hills, and can still slow down. I get 400ks to the tank as the Odometer reads, but that's actually 440k's cause it's 10% out

Before the Tyres, before even the extractors, when I just had the rampod, I was getting 550k's to a tanks...even got 600 once...

Little changes can make huge differences...

s its possible that my engine is infact ok... well damn.. i wanted more power... not less! lol... i went from 205-70R15 to 235-75R15 mud tires... so i dont think thats too much of a differance is it? hmmm.. very interesting though... how do i make sure my engine is running at it's peak performance? jus to be sure?

Whenever you do any major power affecting mods it is best to leave the battery on the car totally disconnected for 1 night.

Then when it's connected back up, take it for a long drive, both traffic and highway runs are idea. The reason behind this is the ECU will has been reset and will start calculating all it's engine management details all over again...helps a bit.

It could also simply need a bit of a tune up, could be running rich etc...

note.. it has HAD a tune up... a full tune up... when i did the paint job. i'll have to try resetting the chip though.. thats an idea.. but that damn check engine light is still on.. i'm gonna really have to deal with the stupid fault codes.... see what the problem is. IF theres a problem.

I'd definetly check that engine check code. I had one a while back, checked it out, said the Oxygen Sensor was stuffed. Put a new one in and it made a lot of difference!

hmm.. well i've got almost 114,000 miles on my rig... bought it with almost 90,000 miles on it. far as i know. the o2 sensor is the factory default. any idea how long those things last? an i thought that if the o2 sensor was out.. wouldnt it make ur engine run rich? my exhaust is clean from what i can tell.. doesnt smell rich or anything so...

SimplyPV- fix the fault codes with the EFI first, there's no point investigating anything else until the EFI computer is happy!

I think you'll find your tyres will have made a big difference with the performance. I've gone from a 225/70 to a 235/70 (which isn't a big increase- only 15mm diameter) and have noticed the acceleration isn't as good now. You've increased your tyre diameter by nearly 66mm by going from a 205/70 to a 235/75!

i would suggest getting the O2 sensor looked at, i have been informed they are only recommended to last ~100,000k's (i dont know if this is the same for feroza's?)... however, this would suggest its about time for a replacement one.

Man I'm going to get the O2 sensor checked on mine as well. I'm running 31's and if I hit a hill I need to shift down to 3rd to get it up there! and my speedo isn't callibrated either but I'm only getting 330 to 350 to the tank... so about 365 to 385 to the tank.

Need to get it overhauled I guess.

The O2 sensor isn't normally used by EFI systems under full throttle acceleration- fixed "tables" stored in the EFI memory are used in these circumstances. It's function is to control the mixtures when the vehicle is cruising at a fairly constant speed and the EFI is operating in "closed loop" mode.

So, don't expect a power increase from replacing the O2 sensor, but your fuel economy may improve if it is stuffed.

Cheers mate,

Had a look at the service history and along with a lot of other things O2 sensor never changed.

Can't hurt can it now?????

FerociousFeroza wrote:Can't hurt can it now?????

It'll only hurt your wallet!

OK how much do you think is a ball park figure for the O2 sensor????

If it's more than $50 they're dreamin!!!!

All depends on if you can find an aftermarket one made to suit. But I can't see even an aftermarket one being less than $50.

For genuine it wouldn't surprise me if it was over $150.

i've found one from o2sensorworld.com (or somethin like that) for $20.96 (with 5 bucks shipping), us currency. dunno if thats good or bad... gonna wait on an answer before i buy it... i figure i'll jus replace mine anyways.

i priced a new O2 sensor from Daihatsu about 3 months ago, it was around $350 Aus. Not cheap.

Clint wrote:i priced a new O2 sensor from Daihatsu about 3 months ago, it was around $350 Aus. Not cheap.

Ai caramba! That's pricey.... will just have to call on my friend, the master of cards....

Have credit... will purchase.

Google to the rescue!

Bosch make a replacement -

Feroza 10.88 - 12.99 HD-E L300/310 4 cyl. 1.6L Oxygen Sensor 0 258 001 027 Universal Type

Text taken from here: http://www.bosch.com.au/productcatalogu ... ations.pdf

So do NGK:

Applause 1.6 HD-E 6/1989 - 9/1997 OZA401-E70

http://www.ngk.com.au/oxygen_sensor_pas ... ihatsu.htm

So has anyone replaced their oxygen sensor lately?

I need to do some more investigating but I believe mine is stuffed and causing the hesitation that I've been getting. I also had the oxy sensor logged as a fault on the ECU which would back this up.

Anyone priced any of the aftermarket ones? NGK only list a universal one to suit (without the sealed connector which seems like a dumb idea to me...) I noticed they list the same universal one, plus one with the proper sealed connector to suit the Applause though!? From the diagrams it looks like it will fit. Also says it's got a 50cm long lead which is great if you've got extractors .

http://www.ngk.com.au/PartFinder/sensor ... ne=1.6HD-E

Correct me if i'm wrong but can't hesitation under acceleration be caused by, tired spark plug leads, poor contacts in Dizzy cap and rotor button? I know that the dizzy caps are about $69 for daihatsu, mine are really bad and i'm gonna have to replace it soon. I still have to test my leads though.

Dave

Yeah Dave- they could cause it..... but I've already replaced all that stuff with no change.

I've got a spare distributor and there's no difference between the two at all; plus I bought some new Magnecore leads about a month ago and that made no difference to the problem. It does drive a little better with the leads but still dies in the arse sometimes after changing gears.

hey david... did you ever check your fuel fiilter? air filter? theres a pretty good chance that one of the 2 are stuffed up..... since you say it lags when you accelerate.. that would be my best guess... the oxy sensor, you would know it going out by gas mileage dropping pretty steep and running rich or too lean since the oxy sensor only works for the fuel/air ratio mix. i'd check the filters first before replacing the oxy sensor. you also might want to check your third fuel line. the one that goes to the charachol canistor. the reason why i mention this is because if its plugged up, then your fuel tank is not able to presserize it self when fuel is drawn out of the tank, this can cause the fuel pump to struggle to provide fuel. check al these out and let me know what you find out alright? good luck!

Fuel filter should be OK as it was replaced about 15000km ago. I also checked the fuel flow around that time and it was within specs, but could have changed since then. If it was a fuel flow problem I'd expect it to be detonating at higher revs from running lean, but it isn't. Both airfilters I use are near new too.

I drove it around yesterday while monitoring the oxy sensor voltage. It was within spec once warmed up but did appear to be reacting slowly to throttle changes (which is a sign of a stuffed one). Supposedly they only last up to 80000 miles (~130000km) so mine's well and truly past that. As they get older they react slower to A/F ratio changes and can cause "driveability problems" which sounds exactly like what I've got.

Thinking about it the problem began around when I fitted the extractors. I discovered then that the old exhaust manifold somehow wasn't earthed through the engine. This wouldn't be a big deal except that the Feroza runs a single wire oxy sensor and needs the exhaust system to be earthed for it to work. So chances are mine was never working before I fitted the extractors! The EFI computer would have been seeing it as open circuit- but never logged a fault for it.... So, before the extractors were fitted it was never in closed loop.

Now it is earthed through the extractors and sort of working it's causing the problems. I'm going to take it for a drive later today with the oxy sensor disconnected and see what it's like. My bet is it won't log a fault and will drive like it used to- if that does happen I'll buy a new one.

Sure enough, disconnected the oxy sensor and took it for a drive- no surging and the EFI fault lamp on the dash didn't come on.

Most likely it's also the reason I've had detonation problems since day one...

NGK oxy sensor part number OZA401-E70 (with proper waterproof connector only) $58.

That's for the Applause version.... I hope it fits as I've ordered it

OK the Applause oxy sensor OZA401-E70 does fit and the wire length is perfect for anyone with 4-2-1 extractors, if you haven't got extractors you'd just have to coil the wire up. The connector plugs straight into the factory wiring loom's sealed plug (a lot better than having an electrical connection exposed to mud and water like the listed sensor for the Feroza.... )

The only thing I had to do was unbolt the new sensor from a mounting plate it was supplied on- it then screwed straight into the extractors.

Have to wait till tomorrow for the test drive.

All appears to be fixed! It responds a lot better to partial throttle openings and I haven't detected any surging or hesitation.

I'll do a quick "how to" sometime soon on checking out the oxygen sensor using a multimeter.