No check engine light with speedo disconnected?

ericem · Post by **ericem** » Fri Jul 10, 2009 8:53 pm

I am not sure if hooking things up like this work. So I tried lol. Just says reading rom? I am thinking maybe the wire doesn't make contact at the computer end. Should I go buy a female end parrel port? Or am I just doing this all wrong?

ericem · Post by **ericem** » Fri Jul 10, 2009 9:22 pm

Oh and I am reading through your thread vrg3. Seems like a few people had the same issue. Another 10 pages to go!!!

ericem · Post by **ericem** » Fri Jul 10, 2009 10:22 pm

got it working. What a awesome program. Been testing the car for a bit now driving around yet no overheating and fans cycle. How does it measure boost and vacuum ? It does show timing correction as high as 4. Once i fix all my vacuum leaks i will see how things run. I havent driven the car very continuos. Seems like if i let it idle till it is at operating temp its fine. Regardless very cool app thanks alot vrg3!

BSOD2600 · Post by **BSOD2600** » Fri Jul 10, 2009 11:54 pm

ericem wrote:How does it measure boost and vacuum ?

MAP sensor.

ericem wrote:It does show timing correction as high as 4.

I've seen as low as 6-8 with mine, but then again I wasn't data logging purely for the timing either.

Not to negate the work vrg3 has done with b10scan, but the USB evoscan cable/software (or revscan) is a very nice Windows package to data log with also.

ericem · Post by **ericem** » Sat Jul 11, 2009 1:29 am

hey guys i think i have a bad ecu it started doing the thing with the fans running steady but at the same time b10scan stopped showing all information everything went blank maybe a few things showed up scrolling through but would go blank. The temp guage really starts to drop as well. Got my dads $200 temp gun and it showed 140f at all parts of the cooling system and like 160 at the turbo coolant line. So should i definitely look into a new ecu or what ? I am getting no cel btw.

log1call · Post by **log1call** » Sat Jul 11, 2009 5:45 am

I've said it bofore on these forums but....

If you are getting elusive, varying, intermittent codes, or mo codes at all, and the car is a few years old....
Pull the ecu and have a look inside. Look for blown transistors(they can explode a piece out of the side of them), burnt resistors, cracked circuit boards, dry solder joints, leaking capacitors, water damage.
Use a magniying glass and inspect every component, circuit and joint.
It only takes a matter of minutes and given the number of things that can happen inside there, and the number of checks you could have to do to track it to there, it's best to do it earlier than later in the diagnostic process.

ericem · Post by **ericem** » Sun Jul 26, 2009 5:41 am

extremely disappointed right now. Replaced the ecu and things seemed great. Took the car for a drive fans were cycling no issues. Get home pull in the driveway and again they were on waited a good 10 minutes! Also my high idle appears to be totally unrelated to fan cycling because it does high idle even when there working. I feel like dumping the car this is totally pissing me off. I even shut it off and waited a bit turned key to the first notch and them temp gauge fell noticeably yet it kicked on the fans again ! I need to plug in my select monitor again. But there must be something more serious going on. I also tried sanding all grounds and spraying every connector with contact cleaner and used dielectric grease. Is something failsafing possibly related to my high idle ? Can a knock sensor do this in any way ?

ericem · Post by **ericem** » Sun Jul 26, 2009 4:40 pm

Plugged in b10scan. I went through everything was showing normal. I get to CT was blank for a bit. Went through the rest everything else was showing. Came back to CT still blank waited waited something shows up. 203F stays there wait wait rev engine blah blah didn't change at all. Waited and waited. 199F stays there for a few minutes. Temp guage is actually beginning to start going lower noticeably. If I shut off the engine, wait a minute. Turn it to ignition on. Temp guage dipped significantly. Yet on b10 shows 199F and the fans still run. What now? Another CTS?

ericem · Post by **ericem** » Mon Jul 27, 2009 5:46 am

hey guys so got back from a track. Car seems to use just as much gas city or highway ? Also tried the other cts i had same thing. Drive for a bit bam stuck at 203f 199f. Going to do some more grounding tomorrow.

BSOD2600 · Post by **BSOD2600** » Mon Jul 27, 2009 6:27 am

CoolantTemp is always showing in the 200F range, even when engine is cold?

Looking through my RevScan data logs, seems the coolant temp was hovering anywhere from 81C to 95C (178F - 203F) after things were warmed up and before/after pulls.

ericem · Post by **ericem** » Mon Jul 27, 2009 3:45 pm

But with the fans running for like 10 minutes shouldn't they shut off eventually? Right at 189F they shut off. What is weird is how the temp guage itself dips very low after shutting off the car, yet the CT is showing still 199F why would the guage dip like close to the 1/4 mark yet still? I did drop the sensor if it matters? lol. I think I will buy a brand new sensor. Last sensor was out of my 93 legacy which was replaced like early, but I think I dropped that sensor to!!

Post by **Legacy777** » Mon Jul 27, 2009 6:51 pm

Yes, get a brand new sensor and see if that fixes your problems.

ericem · Post by **ericem** » Tue Aug 04, 2009 4:44 am

ok i have the brand new oem sensor in same thing. Idle issue is totally unrelated the the temp sensor as well. When the idle goes up the fans are cycling normally at the same time. Going to get a new knock sensor out curiousity. Already tried replacing the o2 sensor. If the cats were clogged would it cause this issue with my idle wanting to go up to 900 ?

After this going to change my coolant tank to a wrx one and put a 04 wrx intercooler.

Post by **Legacy777** » Tue Aug 04, 2009 4:47 pm

If the cats were clogged that would typically cause sputtering, and you probably wouldn't be able to accelerate/rev the engine very high.

ericem · Post by **ericem** » Tue Aug 04, 2009 10:03 pm

i think the issue with the fans might actually be the coolant tank. Today fans were not cycling while the upper hose on the rad was pressurized the one from the coolant tank to the turbo was not. Drove around eventually caught the fans cycling and at the same time the turbo to coolant tank was pressurized probably stop leak debre floating around. Going to get a wrx tank tonight. Now i am hoping i can make it fit in the stock location.

ericem · Post by **ericem** » Tue Aug 11, 2009 7:08 am

Well replaced the tank with no luck. I wonder if when it detects knocking it defaults to fan on for a bit as a safe mode? Can't believe it just says at 199F reving it steady or w/e. so 3 Temp sensors, few months OEM, non oem brand new, BRAND new OEM. Have a knock sesor and wires coming tomorrow.

Car is extremely sluggish at times and there is 0 overheating issues. All I know is the car definitely seems like it should be faster. Feels like my N/A legacy for some reason alot of times, and the two things I swapped from the N/A legacy right away was the coil pack(diamond), and knock sensor. hmm.

BSOD2600 · Post by **BSOD2600** » Tue Aug 11, 2009 9:06 am

Per the FSM, the radiator fan control takes the input from the water temp sensor, vehicle speed sensor 2 and A/C switch. These signals simultaneously turn On or OFF the main radiator fan and A/C sub fan as well as setting them at HI or LO speed.

Have you independently verified each of those sensors/switches are working properly?

ericem · Post by **ericem** » Tue Aug 11, 2009 4:19 pm

you know what the fans are definitely running while driving even at 100kmh. Maybe no awd and fans not cycling related ? Vss 2 is the one in the speedo or back of tranny ?

ericem · Post by **ericem** » Tue Aug 11, 2009 7:33 pm

Ok lets say the signal drops out randomly is it possibly it defaults to fan on as a safe mode? If i restart the car when the fans are running they shut off and don't come on for a long time. I am not getting a check engine light, but I do get the TCU code of duty solenoid c some times usually if I have been going a constant speed which might be related, but if I move slowly then stop and restart no power light flashing. I guess I better remove the cluster. Is the sensor fixable? I have a spare cluster from my other car but its much higher mileage.

BSOD2600 · Post by **BSOD2600** » Tue Aug 11, 2009 9:25 pm

The vehicle speed sensor 2 is installed onto the transmission case, the signal emitted from it is sent to the ECU and speedometer. the inner shaft in vehicle speed sensor 2 is connected to the speedometer shaft in transmission with plate. The pick-up signal is emitted by the rotation of the shaft.

I *think* the VSS is located under the speedometer housing and is this. Anyone confirm?

ericem · Post by **ericem** » Mon Aug 17, 2009 9:32 pm

Wouldn't it trip a code though? Screw the fans atm lol. I am still going crazy with the idle! If the voltage goes to like 12v should it really bump the idle noticeably?

ericem · Post by **ericem** » Thu Sep 03, 2009 4:48 am

I am pretty sure at this point the issue is my voltage. At idle goes as low as 11.5v in D with the fans on. Once it is in the 11V range for a few seconds bam high idle. Also tried replacing the electronic part of the IAC with the one from my N/A legacy and the shaft spins smooth but still sprayed some cleaner while spinning. Everyone elses car I have tested the lowest it would go is like 12.9v. So I guess assuming the alternator as being bad is a good assumption? Second battery btw. I have a spare reman alternator so ill pop it in when I get a chance. Also did the grounding mod!

ericem · Post by **ericem** » Fri Sep 04, 2009 3:47 am

GRR swapped alternators EXACTLY the same issue. Funny thing is when the fuel pump is loud v is around 13-14v. After driving a bit its like 11.5-11.9v in D and the fuel pump gets quieter. Possible its a bad fuel pump putting to much load? Going to try a friends battery first, if that doesn't work, I guess ill get a stock fuel pump.

ericem · Post by **ericem** » Tue Sep 08, 2009 3:13 am

Why doesn't the check engine light come on when driving without the speedo cable hooked up? Shouldn't it give me a VSS code or something? The light is working not sure wtf. I took apart a bunch of the dash and stuff to replace some bulbs and inspect some wiring and when I went out the speedo wasn't hooked up yet never had a VSS code!

Post by **Legacy777** » Tue Sep 08, 2009 3:05 pm

How long did you drive and wait for the light to come on?

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No check engine light with speedo disconnected?