Hard Start, Changed IACV, Still Hard Start

[brendanr279]

I'll start by saying I really appreciate the help all you folks give on this forum...  Here we go...  Again.

 

92 Legacy L, 2.2 L.  75000 miles.  My car has been starting hard for a couple years now, progressively getting worse.  At first it was only in cold temps, now it's been happening all summer, and starting harder since the cold is setting in.  If the car has been sitting overnight or 8+ hours or so, when I go to start it, it immediately putters out until the 3rd or 4th attempt, and only with me pumping or pressing the gas pedal.  Once it's had that first bit of a start up, it'll start no problem, no gas pedal needed, until it sits for a while again.  

 

Check engine light has been on for a while.

 

I cleaned the Idle Air Control Valve once with carb cleaner, just spraying into the opening and letting it drain, repeating once or twice.  I didn't unscrew the top of the valve cover though and really get into it.  That didn't fix it.  I bought a used IACV on ebay, cleaned it the same way, still having the same problem. The hoses attaching to the IAVC all appear in good working condition. The car runs normal once it's started, the idle level is fine, with no "searching".  I've used some fuel injector cleaner occasionally.  I change my fuel filter regularly.  I don't notice any loss of power at any point once it's running.  What's the deal??

[PA Grown]

Weak fuel pump? Turn the ignition on and crack open the cold start line to the injectors, if there's no gas that spills out you gotta problem.

[1 Lucky Texan]

next time you feel certain this will happen, just press the gas pedal to the floor, and hold it there (that's 'clear flood' mode) while cranking. If it seems to start fairly well, you may have an injector leaking into a cyl.

 

then, next morning, start pulling plugs to find which cyl is wet with fuel.

 

engine temp sensor is another possibility, but remote I guess.

Edited October 31, 2014 by 1 Lucky Texan

[PA Grown]

If he had a leaking injector the engine would reek of gasoline. But a possibility.

[porcupine73]

You mentioned the CEL/MIl has been on for a while. What code(s) are flashed out?

[brendanr279]

I don't smell fuel, and I'm pretty sure at times I do try to start it "clear flood" mode and it doesn't seem to start much easier.  I'm not sure what code it's giving.  Last spring when I had it at the shop they said it was the IACV, they tried to order the part used but couldn't, so they said they cleaned it instead.  Still didn't start well.  

[1 Lucky Texan]

maybe some gummy deposits in the throttlebody? they might behave as outlined with temperature - but the problem seems very severe.....

[heartless]

you need to find out what the codes are - complete instructions found here: http://legacycentral.org/library/literature/codes.htm

 

if it is the IACV it can be cleaned - a search here should turn up some more info about that.

 

hard starting is very often related to the coolant temp sensor for the ECU - fairly cheap part, not terribly difficult to change, but a little awkward due to location.

[Bushwick]

Has the fuel filter ever been changed? Open the hood, look on your right to the side of the driver-side strut tower. There's a canister that looks similar to an oil filter with an inlet and outlet. There's a clamp holding into place. Auto parts stores sell them for $15 roughly IIRC. With engine OFF and neg. battery terminal disconnected, remove the filter; it'll seep some gas, and might spray a little. Wrap it with a rag, and hold a rag over the hose and the nipple. Break the seal with a small flathead screwdriver. The rag will catch the spray. Remove old filter paying attention to which hose is which. The new filter will have flow orientation and an "arrow" embossed into the casing. The arrow points toward the engine i.e. the gas tank will enter the filter, the filter outlet will enter the engine. I suggest cutting the first 1/4" off the hoses so they'll seat tightly on the new filter. Tighten the clamps. Don't go overboard if the they are worm style clamps as they damage the hose; should use actual fuel line clamps with a 100% smooth banding to prevent eating into the hose, along with 100% uniform clamping, so buy some!

 

After checking everything is reconnected, I suggest turning the key to "ON" a couple times before starting to prime the empty fuel filter. Start the car and immediately check for leaks. Let it run for 5 minutes and make sure no leaks are present. Shut it off, and try restarting. Let it get completely cold and sit for several hours, then check if it'll start or not.

 

EDIT: Get the code pulled. Also, if you pull the neg. terminal and do replace the filter, it'll reset the codes.

Edited November 1, 2014 by Bushwick

[brendanr279]

Update on the situation...   I've tried starting it with the gas pedal held to the floor.  It won't start easy, pumping the gas definitely helps it start easier.  And I was wrong, I can smell a bit of fuel now that you mention it.  It's not very strong though and it goes away.  Another thing i forgot to mention is that once it gets started, the first time I need the car to move (unless its been thoroughly warmed up) it will lack power, then lurch for maybe the first 25-30 feet of driving.  then It works itself out and is fine. 

[1 Lucky Texan]

get the codes read and post them here. Parts stores will read them. Or, if you have a smartphone, get am elm327 BT adaptor and the Torque app.

 

doesn't seem like it's flooded if holding the pedal on the floor while cranking doesn't help.

 

So, you smell fuel though. leaking injector or some other leak is possible I guess.

 

next time you feel it will fail, try cycling the key from OFF to ON - wait 8 seconds, back to OFF, then ON - wait 8 seconds, do that 3-4 times, THEN START. This sould gurantee the pump has fully pressured the rails.

[Bushwick]

On fuel injected cars you shouldn't be touching the gas pedal during start up unless doing a diagnostic procedure. On engines with a carb it's a different story. IF it was a leaky injector, and gas was pooling in a cylinder (or 2), the engine would just crank a while before starting. IF you are pressing the pedal during cranking, you are introducing MORE gas into the cylinder before it's even fired.

 

 

With all that said, if the engine is running rougher or having a harder time starting, it sounds like there's a bad wire/connection/short somewhere and one of the senors (O2, coil, etc.) that you recently messed with is the culprit.

[1 Lucky Texan]

On fuel injected cars you shouldn't be touching the gas pedal during start up unless doing a diagnostic procedure. On engines with a carb it's a different story. IF it was a leaky injector, and gas was pooling in a cylinder (or 2), the engine would just crank a while before starting. IF you are pressing the pedal during cranking, you are introducing MORE gas into the cylinder before it's even fired.

 

 

With all that said, if the engine is running rougher or having a harder time starting, it sounds like there's a bad wire/connection/short somewhere and one of the senors (O2, coil, etc.) that you recently messed with is the culprit.

 

 

well, I'm not sure about 'pumping' - it could confuse the ECU with crazy TPS readings.

 

But, it's my understanding, that holding the pedal on the floor is detected by the ECU as a 'clear flood' command and it will withhold fuel to help lean-out the combustion charge.

[Bushwick]

Right, if he's doing a diagnostic test, but he shouldn't need to do this every time the car starts. A bad connection, bad CPS, grounded O2, etc. can all affect the way an engine starts or not starts, or how it'll run. If he's pressing the pedal and the engine isn't flooded, it will add gas to cylinder during the initial pressing.

 

 

Try this to rule out the injectors leaking, disconnect the fuel pump fuse and let the engine stall. Turn the key OFF. (can go a step further and bleed the gas out of the fuel line nozzle that looks like a tire valve stem to be 100% certain no gas pressure is left between the fuel injector and the regulator in the fuel rail; use a rag to prevent possible spraying). Leave the fuse out. Let engine sit overnight or however long it usually sits. Clear the code with a hard reset. Put the fuse back in, turn key to "ON" but don't start. wait a few seconds then turn "OFF". Do this 2 more times then crank w/o touching the gas pedal. It should start right away as it won't be "flooded" since the injectors had no gas in them. If it cranks like before (still don't press the gas pedal) then start looking at the sensors or wires that were touched before. Another way to test is connect a fuel pressure gauge and observe if the pressure in the line drops excessively, which could indicate the fuel is entering the cylinder while sitting. Another way to check if the engine is actually flooded is to pull the plugs and check if they are wet. 

 

A faulty O2, faulty CPS, etc. can all have intermittent issues that will make you run in circles thinking something else is wrong.

Edited November 3, 2014 by Bushwick

[heartless]

92 Legacy L, 2.2 L.  75000 miles.....

 

Check engine light has been on for a while.

 

 

you need to find out what the codes are - complete instructions found here: http://legacycentral.org/library/literature/codes.htm

 

follow the directions in the link and find out what code (or codes) are. The CEL is on for a reason, find out what that reason is.

we can all play "guess the problem" for days, but the code(s) will give you a definite direction to work on resolving the problem.

[Bushwick]

Sorry, I got this thread mixed up with another one I thought I was replying to where the guy had already pulled a P0304 with his own scanner and was dealing with more of misfire scenario. 

 

 

 

This sounds more like a fuel pump failing. Go to Auto Zone and ask them to pull the codes. I suggest insisting on them letting YOU attach the code scanner as they often insert the plug hastily at an angle, which can force the OBD connector prongs out. Just make sure the scanner plug is perfectly straight when being inserted and you are good. I've had 2 different cars that mysteriously ended up with a "no connection" after having been OK previously, and it was traced back to rushed AZ workers.

Edited November 4, 2014 by Bushwick

[heartless]

Bushwick - the car is a 92 - OBDI - codes need to be read the old fashioned way...link to "how to" directions has been provided...

[Bushwick]

Was there any year OBDI that could be pulled with a scanner? I didn't realize early 90's Subaru relied on the flashing CEL. Last car I had pre OBDII was a 92' SHO and I seem to remember that being code readable, so it didn't dawn on me these were different (hence I hadn't bothered with the link) 

[heartless]

90-94 Legacys did not have an OBDII scanner connector. 95 was the first year for that.

 

I think there was a hookup for the Subaur Select monitor on the earlier models, but that is pretty much a dealer thing - not something that the chain parts stores are going to be able to do.

 

Nope, the OP is gonna have to get the codes to flash thru the CEL if they want to know what they are, which is why I provided the link to the instructions on how to do it. That link saved me time, and headaches, when I had my 1990.