25 replies to this topic

[Crawlerdan]

ive owned 109 subarus, this ones weird for sure

1992 legacy auto fwd

will not start

belongs to a friend, said that it wouldnt start, hit it with starting fluid for a few weeks, and that worked, now that doesnt work


ive noticed the following-brand new coolant temp sensor
both fans on, all the time, running or not, cold or hot
iac valve doesnt look horrible, but.....
it has spark, getting fuel. compression is 125ish at all 4

i got it to start tonight- horrible shuddering idle, but all 4 firing, idle at 2k rpm, will restart fine after its warm. but cold start is a no go


maybe timing skipped a tooth?.....odd one

what thinks the land of soobies:D

[Ricearu]

Maybe a bad mass airflow sensor? just maybe. unplug it and see if it acts any different. I have seen a bad maf make a car run real funny.

in fact thinking back, spraying starting fluid may have actually done the hot wire filament in the maf in for good. they can't take the solvents.

Edited by Ricearu, 08 November 2012 - 11:39 PM.

[1 Lucky Texan]

ive owned 109 subarus, this ones weird for sure

1992 legacy auto fwd

will not start

belongs to a friend, said that it wouldnt start, hit it with starting fluid for a few weeks, and that worked, now that doesnt work


ive noticed the following-brand new coolant temp sensor
both fans on, all the time, running or not, cold or hot
iac valve doesnt look horrible, but.....
it has spark, getting fuel. compression is 125ish at all 4

i got it to start tonight- horrible shuddering idle, but all 4 firing, idle at 2k rpm, will restart fine after its warm. but cold start is a no go


maybe timing skipped a tooth?.....odd one

what thinks the land of soobies:D

i'd say your skipped tooth is a possibility - especially if it seems doggy when driven.

[johnceggleston]

check the timing and try it with the coolant temp sensor unplugged.

[porcupine73]

Hm yes at the least the both fans staying on all the time is suspicious. I know it will do that as a failsafe if the sensor is disconnected. But if that sensor is way out of spec and the ECU thinks the coolant temp is actually say 205F when it is really 30F it's probably not going to inject enough fuel for it to run, so maybe the starter fluid helps it out a bit. That might also explain why it will restart ok if the engine is warm.

[Fairtax4me]

No CEL?
Which temp sensor is new? The one wire or the two wire?
Checked the test mode plugs under the dash?

[Crawlerdan]

Maybe a bad mass airflow sensor? just maybe. unplug it and see if it acts any different. I have seen a bad maf make a car run real funny.

in fact thinking back, spraying starting fluid may have actually done the hot wire filament in the maf in for good. they can't take the solvents.

i thought this also, i have a good one on hand, no change

[Crawlerdan]

No CEL?
Which temp sensor is new? The one wire or the two wire?
Checked the test mode plugs under the dash?

the two wire is new, no cel....but not light at all, bad bulb or no bulb i suspect;) will update

[Fairtax4me]

I would check for codes first, and also check the green test mode and black? diagnostic/reset plugs under the dash. They should both be unplugged.

[Crawlerdan]

someone pulled the CEL bulb, haha

21
22
24
30
31
32
49

[1 Lucky Texan]

1988 and later models with Multi-Point Fuel Injection (including Legacy)
11 Crank angle sensor or circuit
12 Starter switch or circuit
13 Cam position sensor or circuit (TDC sensor on Justy)
14 Fuel injector no. 1 (Legacy, Impreza, Justy, SVX); Fuel injector 1 and 2 (XT, Loyale, GL, DL)
15 Fuel injector no. 2 (Legacy, Impreza, Justy, SVX); Fuel injector 3 and 4 (Loyale, GL, DL); Fuel injector 5 and 6 (XT6)
16 Fuel injector no. 3 (Legacy, Impreza, Justy, SVX); Fuel injector 3 and 4 (XT)
17 Fuel injector no. 4 (Legacy, Impreza, SVX); Fuel injector 1 and 2 (XT6)
18 Fuel injector no. 5 (SVX)
19 Fuel injector no. 6 (SVX)
21 Coolant temperature sensor or circuit
22 Knock sensor or circuit (right side on SVX)
23 Air flow meter or circuit (exc. Justy); Pressure sensor (Justy)
24 Air control valve or circuit (exc. Justy); Idle speed control solenoid valve (Justy)
25 Fuel Injector 3 and 4 (XT6)
26 Air temperature sensor (Justy)
28 Knock sensor no. 2 (SVX, left side)
29 Crank angle sensor (SVX, no. 2)
31 Throttle position sensor or circuit
32 Oxygen sensor or circuit (no. 1, right side on SVX)
33 Vehicle speed sensor (VSS) or circuit
34 EGR solenoid valve
35 Canister purge solenoid or circuit
36 Air suction solenoid valve (Impreza); Igniter circuit (Justy)
37 Oxygen sensor (no. 2, left side , SVX)
38 Engine torque control (SVX)
41 Air/fuel adaptive control
42 Idle switch or circuit
43 Throttle switch (Justy)
44 Wastegate duty solenoid (turbo)
45 Pressure duty solenoid (turbo)/atmospheric pressure sensor circuit (non-turbo)
49 Airflow sensor
51 Neutral switch (manual transmission)/inhibitor switch (automatic transmission)
52 Parking brake switch (exc. Justy)/Clutch switch (Justy)
55 EGR temperature sensor
56 EGR system
61 Parking brake switch (Loyale)/Fuel tank pressure control solenoid valve (Impreza)
62 Fuel temperature sensor (Impreza)/Electric load signal (Justy)
63 Fuel tank pressure sensor (Impreza)/Blower fan switch (Justy)
65 Vacuum pressure sensor


your 30 is weird, at least, there's no 30 for any soob at the above site.

clear them out and see which ones come back immediately.

from troublecodes.net

Edited by 1 Lucky Texan, 09 November 2012 - 11:32 AM.

[Ricearu]

reset and see what reappears. If they all reappear, then you may have a bad ECU, not sending out it's 5vdc reference signal. all those sensors besides the 02, run on 5v. Also, you could have a bad ground to or in the ecu.

[Crawlerdan]

i cleared the, only one that came back right away was IAC Valve, i cleaned it- we'll see what that does

[Fairtax4me]

Kinda seems like someone went along unplugging sensors to see what would happen. Or someone had the engine out and left the main harness unplugged.

If the ECU gets no signal from the crank sensor you get no spark. They typically fail intermittently only when warm. If it were bad I would expect the engine to not start at all.

[Crawlerdan]

ok guys- i hate seeing things left unanswered.i fixed it

i removed the iac, thoroughly cleaned it with brakleen, sea-foamed it and the car, reset the ecu. problem solved. started in 3 cranks at 12deg this morning

[wentz912]

Does the IAC affect warmed up engine operation at all? Have a miss/stumble that only appears after the engine has warmed up. Occasionally throws a code for misfire on #2 and #3

[Fairtax4me]

Iac doesn't typically cause misfires. When is the last time you did a tune up?

[Crazyeights]

Have you verified that the fuel pressure is correct with gauge?

[wentz912]

Have brand new NGK plugs and wires, as well as a diffrerent coil off another car. Also brand new fuel filter and oil change.

Thing runs fine most of the time, just seems to stumble when loaded at lower rpm's after warmed up. If I punch it , it will burble through the stumble and pull just fine.

It's the damnedest thing, can't figure it out.

[Fairtax4me]

Could be a bad o2 sensor. Might try cleaning the MAF sensor if it has it. PCV valves are known to cause strange issues as well so if that hasn't been replaced it should be.
Make sure all vacuum hoses are in good shape and the breather and PCV hoses are clear of obstruction and connected properly.

One other option is the timing belt. If it has jumped one tooth the car may still run fine cold but have issues when warm.

[wentz912]

It's a 96, so it is an MAF car, will jump on the pcv change. Have checked timing several times and is still dead nuts. Easy yo check since im coverless

[porcupine73]

Maybe unplugging the front o2 sensor connector and then see if the same thing happens or not after it warms up. That way if it doesn't do it after it warms up with the front o2 unhooked that might be your issue.

[Fairtax4me]

It's a 96, so it is an MAF car, will jump on the pcv change. Have checked timing several times and is still dead nuts. Easy yo check since im coverless

Do you have a scanner that can read live data, or display freeze frame data?

[wentz912]

I don't have a scanner at all. When I get back to town I will see if the guy with a scanner I know, if his is capable of that.

Just so I understand, what am I looking for?

[Fairtax4me]

Basically anything out of the ordinary. Are the O2 voltages within spec? (The front sensor, Bank 1 sensor 1, is the one that controls fuel/air mixture).
Fuel trims should be somewhere around 10% to -10%. (The reading will be positive or negative depending on if the ecu is adjusting towards rich or lean A/F ratio. Beyond 10% can mean the sensor is bad.
Are any other sensor readings out of spec? Coolant temp, MAP/baro pressure/vacuum, MAF flow rate, that sort of thing.