1UZ and IM240 Emissions Test for Engineering

[dumbass]

U need cats with around 400 dpi or whatever they call it
Something to do with holes per unit
Anyway when I do late model cars and they have to pass emissions
I tell customer to tell the exhaust shop that it has to pass today's emissions
Unfortunately half the exhaust shops are stupid
U sort or need euro 4 or 5 cats
Most good exhaust shops will know what that all means

[Sciflyer]

Also, in my experience, these engines will sit smack on 14.7:1 AFR (with good o2 sensors) for almost all conditions at low throttle.
At about 30-40% throttle they'll begin to go richer (13:1ish), and then as you squeeze the throttle they'll go richer again.

What this converts to in lambda I have no idea.

I agree, when i said they run lean-ish i meant that in relation to ideal AFR for power

And at the other end of the spectrum my completely stock, low km Soarer was reading sub 11:1 AFRs at WOT...

[marc280]

Ok I think I've worked out what the issue is... Pulling codes from the ecu was a little tricky as the wires to the diagnostic plug are cut at the ecu, but I shorted Te1 to E1 at the ecu and then connected a test light to pin 6 of the 40 pin plug (the 'W' signal). When doing this to get the codes the light just stayed on. According to the lexls site this.indicates ecu problems which is what I was thinking maybe be the problem.

I pulled the ecu apart and found that 7 of 9 of the larger 'can' type capacitors were leaking pretty badly. I've seen that this can be a common problem, so I really should have checked it earlier. So I've removed all 9 caps as a precaution and will be going to jaycar to see if I can get some replacements.

Before I welded in the cats the idle was working perfectly although i did remember after welding that I forgot to disconnect the battery before tacking the exhaust in the car so maybe I did some damage to the ecu from the welder? Although looking at the leaky caps it seems like they have been like that for a while. Two of.the caps look like they have caused a bit of corrosion on some other components nearby, so hopefully is hasn't caused other problems.

I'll report back once I've replaced the caps.

[dumbass]

i just had to repair a soarer 1uz ecu
shitloads of caps compared to other ecus
unfortunately it didnt fix the ecu
there is one cap u cant get too as its under the alloy near the plug
there is 4 or 5 different values u need
i cant remember if jaycar has them all as there one or two weird values
hopefully they will

[marc280]

Thanks for the tip about the one that is hard to get too, I'll have to make sure that I got them all. I went to Jaycar and you're right, they didn't have all the values that I was looking for. I found the website Mouser Electronics and it looks like they have the exact same brand of caps in all sorts of values, but there are too many to choose from! By looking at the side of the caps that I pulled out they are a PF series (it says PF(M) on the side), but going by the website this series are all obselete as shown in the link below

http://au.mouser.com/Nichicon/Alumin...Z75hqwZ1z0ynpo

Are there any electronic gurus who know what would be an equivalent one? There are heaps of different series all with the same values, so I'm assuming they must behave a little differently. Seeing how sensitive the ECU seems to be to these, I figure it will be important to get the right ones...

[marc280]

I worked out what the series thing is about, apparently PF series had lead in them, so they are no longer used. I found there is a BT series that has a higher temp rating and specifically mentions use in auotomotive electronics for longer reliability which sounds good to me. Only problem is that Mouser side has a $39 minimum charge for shipping. RS Components also sells them but only in packs of 5 or 10 and they are pricey... From RS it would be over $50 just for the caps.

Don't suppose anyone else is in the market for caps to split the mouser shipping

[bimbo]

I might be interested in some caps, will have a looksy in my ecu and see what sort of nick it is in. I am very interested to hear how you get on with your emissions testing as once I have finished building my ute up I will probably have to get it done as well - bit of a PITA as I am in Newcastle and would either have to drive or trailer it down and back - even more of a PITA if I have to do it more than once. Apparently even if I move the cats further back than where they where originally I probably have to get it done grrrr

Cheers
James

[dumbass]

i buy them in packs of 100
39 bucks freight thats nothing
just dont buy a case of beer this week

[marc280]

Success! I replaced all of the caps (ended up ordering them from Mouser) and now the idle speed control works perfectly and the AFR's seem much better! You can now actually watch the wideband display and see the feedback from the O2 sensors helping with the computer trimming the AFR's back to lambda 1 (14.7:1 AFR) at idle and on steady throttle. Under heavy and WOT acceleration it goes to about 0.8 (about 11.8:1 AFR) which is nice and rich like all factory Toyotas tend to do.

The caps I ended up using are the 'PJ' series Nichicon caps as these are supposed to be the replacement series for the old PF series. After doing some researching on-line it seems that leaking caps are a very common problem on many cars that are about this old. Apparently there are many other types/brands of caps that will work but I wanted to stay as close to the design that was there becuase the ECU seems very sensitive to these caps. From what I've read it seems the important thing is that they have low ESR (Equivalent Series Resistance) as from my understanding this means that they can handle higher ripple currents without overheating (that could be completely wrong though...). There is a list of caps with low ESR that should work here

http://www.badcaps.net/forum/showthread.php?t=921

And for a good overview of the Nichicon caps take a look here

http://www.nichicon.co.jp/english/pr...ini/pict_f.htm

There is a really good thread over on Club Lexus that runs through all of the issues with leaky caps in these ecu's. One of the guys posting even seems to be an engineer from Nippon Denso and knows his stuff.

http://www.clublexus.com/forums/ls40...capacitor.html

So now I just need to get to the emissions testing station and this time I'm a little more confident/hopeful that it should pass. I have a test booked in for the 19th of December but that probably won't be enough time to get the test and finalised the engineering cert before christmas, so I'll be calling the RTA everyday to try to get an earlier appointment.

To anyone else out there with a 1UZ and running a stock computer, if you haven't checked your ECU for leaky capacitors I'd be doing it now! The engine is also so much more responsive down low now where before I was a little disappointed at how slow to respond it was.

Bimbo if you are interested in some caps I ordered twice what I needed in case anyone else wanted to buy some.

[marc280]

Since the last post on this the ecu that I repaired started playing up again. So either my soldering skills suck and the caps don't have good connections or the board is damaged in some other way. I decided to get a replacement ecu and then I'll hack apart the old one to use it's connector to make a patch harness for the Haltech. After putting in the replacement ecu the car is running perfectly.

I had the IM240 emissions test yesterday and with the new ECU and cats it passed easily! Woo hoo! It nearly even passed on the warm-up run with only the THC going a little over, on the second run it was well under the allowable limits. the results were

1st Run
THC = 1.26 g/km
NOx = 1.70 g/km
CO = 4.2 g/km

2nd Run
THC = 0.37 g/km
NOx = 0.36 g/km
CO = 1.3 g/km

and for reference the allowable limit for an engine of this age is

THC = 0.93 g/km
NOx = 1.93 g/km
CO = 9.3 g/km

It's bit hard to say what effect the cats had on the result compared to the changes in the computer, but seeing how lean the old computer had the engine running, I'd say that the computer probably had the biggest effect. Also there were some people telling me that I'd never get the car to pass with the new high flow cats (they are Magnaflow spun universal cats with 100 cpsi), but I guess this goes to show if the car is running well, there is no reason aftermarket cats can't be used.

Now off to the engineer to try to get the engineering cert finalised!

[George]

btw, your first run's suboptimal results may be due to aged stem seals leaking..so after sitting for a while, there's some oil in combustion chamber

[4th surf]

What you may find is the leaking caps cause the tracks on the "mother board" to degrade so while now a "cap replacement" did do the deed a few years back now sad to say it's a bit hit 'N' miss. Thing might work fine before it's been running for some time and everything gets up to operating temp but after that? Well it gets a mind of its own.

A recent one springs to mind. Usually I leave things such as engineering and cert over to the owner with the Hilux and Surf conversions yet do have an engineer check things before they went out the door. Most of the time nobody bothers with E&C as they just look like any other Hilux or Surf. With one exception.. It's "Big, Black and in your face", owned and driven by a girl with a tailpipe you could park quite a number of small cars in. Well if that aint gunna attract cops I don't know what is. It was going to be defected on noise and lift but she managed to get around that by saying that it was booked into engineering for that and she had to get to work somehow so was given discretion... However the issue was getting past the IM240. I'd had the ECU rebuilt due to other issues by a computer engineer before returning the vehicle to client so no issues there. Trouble was the cats as dumbass has mentioned. We managed to get some UZZ31 cats via this forum, put them on and done. Passed the test, passed the pits and all legit now. In this instance as a timeframe had been given suitable cats were needed PDQ, No stock anywhere of anything new in the country at the time that was suitable and given that aside from those that do the test the average workshop does not have a 4 or 5 gas exhaust analyzer throwing an extra cat in was not an option. The scanner on live data had given all of the right readings but the "Sniffer" had said otherwise. That has to be happy for you to pass