6G Celicas Forums

Ok after doing some looking i noticed that some of my vac lines arent that tight of a fit.
They stay in place but fit kinda loose so i guess ill buy some better vac line an swap back n the old maf an see what happens

So i finally let her run long enough to read a temp she seems to hold steady around 160
an the mass air codes finally poped up so i now know its 100% an issue

Well i got the maf fixed but now if i try an go over about 40-45% throttle she starts to bog down an backfire
With or without the tps plugged in im more than alittle lost at this point
Only other thing doug cant think of is my fuel pressure might not be good enough with he stock gt fuel pump i think

Sorry to hear that. Hopefully it's the fuel pump then. Cars are frustrating at times. Even ones that're stock, much less one with a swap. I hate this for you, hope you can get whatever it is fixed soon.

Ok mr220v thinks if clean the maf an put a fuel pressure regulator in the return line it might fix my problems for good
So far she keeps getting alittle better with each thing he tells me to do

Its almost never one little thing. Always two or more little issues working together to make it run like crap and frustrate any attempts at diagnosing/fixing the issue. I wonder if you can dig up the correct voltages/resistance for the MAF at certain expected airflows and check them against the readings you can pull from the OBDII or Toyota diagnostic port. Usually its rich at an idle and lean(pinging like a mofo) at WOT if the MAF is dirty.

Is your breather hose connected to the intake hose after the MAF? You might try temporarily capping the pcv hose off and seeing if that makes it run a little smoother. Id also double check the electrical connection at the plugs on the MAF and make sure they are super clean. A tiny bit of corrosion on the contacts of the plugs can create a lot of resistance in the circuit. How long did the harness sit for with the contacts exposed to the atmosphere?

This post has been edited by Special_Edy: Apr 16, 2012 - 1:41 PM

Idk about the top half of what you just said lol
But everything is ran after the maf
Im going to give it a good cleaning tomorrow an pick up a new pcv valve too. An see if any of that help
The harness was never left outside uncovered if thats what your asking

If you look at the real time data coming off the OBDII port you can usually see the voltage(I think its voltage not resistance, could be wrong) coming off the MAF. There should be a contact on the diagnostic port for it too if you happen to have one. Anyways, with the engine off, idling and at various rpms you should be able to see a pretty consistant change in voltage. If the voltage doesnt fluctuate or suddenly stops climbing/falling it will alert you that the MAF isnt working right.

As for the electrical contacts, I have an old 81 SECA 750 bike that was always doing weird things. Never could figure out what was going wrong until I unplugged every wire on that thing and filed, sanded, brushed, contact cleaner sprayed, w/e every male and female plug contact on it. Solved all of the little electrical gremlins the bike had and what it boils down to is that unless the plug it 100% airtight sealed for its entire life the moisture in the air will create some nonconductive corrosion on the electrical contacts. If it doesnt look shiny then it isnt clean and that will create a small amount of resistance in the wiring that can throw things off. Just another idea that may or may not help you in your project.

Well ill go buy some contact cleaner tomorrow an see what happens

I know this is a super random question but could my plug wires be going bad an arcing off eachother from being to close together? Like i said super random.
I just remembered having a problem kinda like now in my old integra
It was caused be bad plug wires

Well there are a couple easy ways you can check them.

Easiest test is to examine the spark plug wires with the engine running while its dark outside. Just turn off all the lights with the car in as dark an area as you can find at night and watch for tiny blue flashes. Jiggle the wires around just incase, so all the wire has a chance to touch metal engine.

Another is to do a cylinder balance test, pull a spark plug wire with the engine running and listen to how much it drops the rpm. One cylinder at a time. If any cylinder drops the rpm less than the others you have a weak cylinder there and possible a bad wire. Try to not touch the car just tbe wire while you are doin this test to reduce the risk of getting zapped. Make sure to wear gloves or use a dry rag(oily is fine, just not wet) to grab the spark plug wires and try to only pull the wire just far enough that it misfires the cylinder not totally out of the spark plug tube. Having the sparkplug wire off with the engine running is rough on the coil.

Last test would be to remove each wire and measure resistance between both ends of the wire with a multimeter. Obviously shorter wires will have less resistance but all should be fairly close unless you have a bad plug wire with a broken conductor inside.

If they pass those 3 tests then it should be fine for use. You shouldnt have a bad wire

It sounded earlier like you havent hooked it up to a proper diagnostic scanner. Check engine codes are only the tip of the iceberg when it comes to your OBDII port. You can see real time sensor readings with the engine running and driving around. There will be data pouring out of the ECU like O2 sensor voltage, ignition timing, calculated load percentage, calculated horsepower output, rpms, MAF flow rates, batometric pressure in the intake, fuel trim settings, coolant temperature, intake air temperature. You can find do so much with all that information, the ecu is pretty stupid sometimes when it comes to actually deciding to give you a check engine code. The most awesome thing you could do would be to freeze frame(take a snapshot of) your engine and compare it to the readings off of another vehicle with the same engine set up and a known good engine.

This post has been edited by Special_Edy: Apr 16, 2012 - 4:46 PM

It's always fun to hold onto a bolt and have your GF turn over the car with it above the VC... GF did that to me once. Didn't warn me. Ow.

Ill do what i can of that stuff tonight an see what happens
I dont have my own obd2 scanner yet so i can do all of that

do you have the wiring diagram for the ECU you are using? i have a few i can send to you if you give me your email

No i dont so far mr220v has sent me info as i need it
But my email is chevy_man_43326@yahoo.com

Autozone rents a decent one for $200 maybe $250. The one that you can enter the vehicle information into is a little faster than the Global (universal) one when it comes to the real time data. A hefty deposit fee but you get it back if you return it in 90 days. You will probably be able to chase down all your problems real quick when you get it. Or you could ask to use the 'store use' one that they use and run it in the parking lot to look for any obvious problems

I got a friend that owns a used car lot that has 2 of them so im gonna see kf i can barrow one for a day or 2 this weekend

Well i cleaned the maf an put in a new pcv valve and.................i had to leave for work so i have no clue if it helped at all. She does seem to rev alot more freely than before but i still get a backfire an smells like shes running rich it i try to rev to wot so i figure im going to try an chip away at my codes an go from there
Ill post a list tomorrow of what they are an see if you guys got any ideas

Anyone know if a bad speed sensor can screw up the way a yota runs
I know some cars will go crazy without it an others could care less lol
Oh thats one of the codes im getting

I would say that a manual transmission ECU could care less but an automatic transmission ECU would be trying to use the TPS and VSS to calculate gear selection. Its prolly going nuts trying to figure out what gear its supposed to be in. Then you get into 'limp to the repair shop' mode with all the AT sensors missing. Gotta get your ECU situation figured out

Im gonna try an figure out the speex sensor an trans codes
I dont understand why my speed sensor isnt working
It was working preswap but not now