upgraded 4age runs just not great.

[DeftAnesthetik]

It runs....... just not very well.

the subject: 1986 mr2, bigport 4age.

the story: engine had a few mods already done by previous owner and me, nothing of real consequence, more reliabity stuff than anything. in the last month i have accompished quite a bit. I installed quads from 4age Silvertop a few weeks ago and was able to get them running quite decently, though it did seem like the engine was leaning out and did not have the power it had before. Now i know quads alone are not going to increase the overall power of the engine so I also have in my possession a set of highcomp injectors, HKS camshafts and HKS valve springs. Yesterday i get myself trenched in early in the morning to get these swapped in..... end of day i had it all done, also replaced the timing and alternator belts(since i was in there anyways) I made ABSOLUTELY CERTAIN that every thing was set for TDC before reinstallation. I did not degree the cams only lined up according to the BGB. lined up dimples on dizzy. everything gets torqued to spec. turned over a few times and fired up. HOOORAY! turn off, jumper T+E fire up set timing 10 degrees btdc, off, remove jumper, fire up, check timing.....Yup ~15 degrees. adjust my idle to about 1000rpm. and im off.

so im driving now, BUT...... NO power in 1st gear at all, 2nd gear is OK it actually responds when you put your foot down, 3rd gear is the same as 1st, RPM's slowly creep upward.

I am i missing something... I followed the manual incase i might miss something, its not the first time i've done work like this on a car, first time for this car though.

i dunno, maybe the injectors are too big and overfueling? from ebay said to be 213cc, i'm upgrading from the dark-blue single nozzle ones which i believe are 185cc. the only reason i changed them is like i said earlier, seemed to be leaning out with the quads already and then with cams getting upgraded it would be even worse.

for the cams i put a 264 duration 8.35mm lift on the intake and a 256 8.35 on the exhaust.

any help would be greatly appreciated and repped where applicable.

[oldcorollas]

with stock ECU?
AFM or MAP?

any chance you can stick an O2 sensor up the tail pipe... or even just measure the voltage on your stock O2 sensor? that will at least tell you if it is above or below stoich (or better with wideband)

[DeftAnesthetik]

with stock ECU?
AFM or MAP?

any chance you can stick an O2 sensor up the tail pipe... or even just measure the voltage on your stock O2 sensor? that will at least tell you if it is above or below stoich (or better with wideband)

Yeah, stock ECU...... before anyone comments YES i have an aftermarket controller to put on here and NO im not going to. Even though it will not be perfect i believe the stock ECU will do what i want it to.

AFM, more a pain in the ass since its goes on and off so many times (being in the way) but "SHOULD" let me run the bigger cams with less effort.

can you save me the trouble of looking and tell me what voltage i should be looking for optimal and if it would be higher or lower for a rich mixture.

thanks

[oldcorollas]

AFM should make it easier.. ish

a stock narrow band sensor (is yours heated?) should read 0.5v at stoich..
but since they are effectively a switch, for rich, you would see maybe 0.7V and lean, 0.3?
if it is not warm enough, then voltage will be low...
if the ECU is doing it'S closed loop thing during cruise, you should see the voltage go up and down every few seconds?

if you can stick in a heated sensor (any generic 4 wire one), they heat up after about 30sec and give a much more stable reading...
when i used a bosch 4 wire for tuning, i aimed aroun d0.7 or 0.75V and that ended up being about 12:1..
but it is different for each different sensor... (could be 0.6V, could be 0.8V)

[DeftAnesthetik]

I think i have a 4 wire around the shop somewhere..... can i just shove it up the tail pipe or should install it where the o2 normally is? the stock one is only single wire.

im sure its best to monitor this while driving but can i just put the car in neutral and "free rev" to see whats happening?

EDIT: Ive been thinking about how to adjust this after I find out whats happening. Just wondering if anyone has tried this --> http://www.4age.net/tech/efimod.htm and what kind of results they got.

[oldcorollas]

best to put it in the original location. the output will be same.. just the 4 wire will be better,

you will need to add a ground wire for the signal to the ECU grounding point, and also heater/ground (seperate one) for the heater. heater pulls 1-4amps and is IGN switched.

you could free rev, but then it gives you no info about engine with any load. you can start in shop, and that might tell you if it is going in closed loop (say by holding at 3Krpm).

modding the water temp sensor puts it into "arm up mode" which is a realyl crap way to do it, as it will change ignition timing as well...
maybe better to mod the air temp sensor output instead? but you are limited to what the ECU decides to do with those different temps..

[DeftAnesthetik]

been buggin at this for the last few hours and after getting a second "first hand" opinion i dont think im overfueling as im not smelling any fuel.... still could be a problem though i guess.

last night i took for a spin and could not push the car over 80km/hr REALLY slow to get moving (10+ seconds to clear an intersection.....SCARY) i checked the CEL codes after i got back and got a code 11 which is supposedly a switch signal problem from A/C or IDL on the TPS (my reference)... since i dont have an A/C model i figure TPS.....

now back to a while ago when i put the quads on originally. I had wired the TPS as suggested HERE (step 11) I found this to be incorrect as with it wired in reverse when you would rev the engine it would rev slowly blow out TONS of smoke and backfire when you let off the gas. When i wired it "normally" (wire color to wire color) it revved fine and no smoke, it still backfired when letting off the gas but i found that problem was from not having the stop screws/dashpot/vacuum hooked up properly and has been fixed.

everytime i have adjusted the idle stops ive gone and checked the TPS....... i think im doing it right but im not 100% since i just just been sticking the multimeter on pin 1 and pin 2 of the TPS and adjusting (counterclockwise) until i get a jump in resistance and securing it there. this has worked fine up until the cams, and injectors were changed. everything has been soldered and wrapped... i've double checked the wiring with the 20v and 16v wiring diagrams (toyota) and even gone as far as to pull the lid off my ecu, its all wired as I THINK it should be: E2 - E2, IDL - IDL, VTA - VTA, VC - VC. I'm headed back out to the shop now, ive got procedures for testing the TPS in my hand (taken from BLACKTOP manual) and im gonna run down it to see if the TPS is faulty. I will be back in to see if anyone has commented.

thanks in advance

EDIT: TPS is fine and adjusted correctly... as long as its wired right.

anyone?

[DeftAnesthetik]

also found this on the old forums, seems to describe my problems as well.....
http://forums.toymods.org.au/index.p...t=0#msg_833710

[takai]

I had symptoms like in 4 different circumstances:

1. 4AGZE - Intake vac/boost leak, meant that ignition advance was wandering
2. 4AGE - Dodgy dizzy wiring, meant that ignition was being triggered off the 180* opposing sensor, which is a more innacurate reading.
3. 4AGE - TPS failed on the quads, kept triggering IDL as well as a value on the TPS
4. 4AGE - bearing in the dizzy failed, false triggering of the ignitors.

All of which points to something being out with the igniton systems, could be the exhaust cam being a tooth out...

[DeftAnesthetik]

well... having been at it most of the day, double, triple and even quadruple checking just about everything EXCEPT the timing belt... I know my next move but it will have to wait until after work tomorrow.

[DeftAnesthetik]

AAAAnGEr , well timing belt WAS off musta slipped before i got tension on, its been fixed (and triple checked), dizzy has been aligned (and triple checked), timing has been set (and triple checked) and this beast is still tame to the point of lame.... it moves but sooooo sluggishly. it does backfire a little at low throttle again..... ive tried running with and without the TPS and o2 sensors, still nothing. To top it off it idles and sounds amazing..... grrr

any advice left before i go back inside this thing??? im getting desperate.

[DeftAnesthetik]

I had symptoms like in 4 different circumstances:
All of which points to something being out with the igniton systems, could be the exhaust cam being a tooth out...

Is it possible for the gear(the one that drives the dizzy on the cam to come loose/out of alignment? I noticed on the cams before putting them in that the gear was a separate hunk of metal unlike the stock cam.... i dunno, like i said im getting desperate

[Joshstix]

If you're not going to do something about getting fueling and timing correct for the package it's not going to be worth the effort for you or for others to try and help you.

[oldcorollas]

first thing is to measure AFR with a 4 wire.. at least then you know if your fuel is rich or lean.

if that is ok, next is to chuck it on dyno/rolling road with a wideband and see what it is doing under load.

if that is ok, the put timing light on and try to see what timing is doing under load..

by changing the induction method, as well as cams, you may have changed to timing requirements more than a little..

either that or you have a mechanical/electrical problem


whu? the dizzy drive gear is seperate to the cam itself??? can you take a pic? i've never seen any cams from differen tmakers (on yahoo at least) which do that..

oh, regarding injectors.. what did you do about the impedance? what is the difference in flow? are you 100% sure of the flow rate?
you really need to get an air fuel ratio measuring device onto it before you try to do anything else..

[Sam_Q]

dont you need a wideband to measure if its rich or lean past the small 14.7:1 window?