Engine Shuddering from a Stop

Goliath · 10-09-2011, 02:39 PM

I've only had my Alero (2.4L Quad 4) for a little over 3 months now, and I'm having a couple problems.

I have a coolant leak somewhere, which isn't a huge deal.... I just haven't been able to find it. But I'm also having some problems with accelerating. When I accelerate from a stop the engine hesitates and shudders. Most of the time it works its way through it, but once it stalled on me.

I've done some reading and it seems like a number of things could cause this; Misfire (but the check engine light isn't flashing), MAF sensor, bad motor mount, tranny problems, and a couple others.

I'm going to start with the easy things first (changing the plugs, checking the mounts, etc)... But I figured I would ask if this is a common problem with Alero's. If so, what usually causes it?

Papa Rad17 · 10-09-2011, 02:57 PM

Ion or white rider are probably your guys. id say thats a good place to start though. would it be anything in fuel delivery system maybe?

03glgold · 10-09-2011, 03:03 PM

just out of curiosity have u checked to see if your oil has a white film in it...not completely sure but i think if you had a blown head gasket it could possibly cause this problem...That would explain lost coolant...I would wait for someone who has more experience to chime in before deciding that you def. have a bad head gasket but you could still look for the film

[ion] C2 · 10-09-2011, 03:20 PM

Take out the spark plugs.

Look at the plug tips for anything unusual (wetness, dark, burnt or chipped off pieces), and look at the plug ceramic to see if there is any hairline cracks in it.
Use a flashlight and look inside the spark plug hole to see if you notice any wetness (a slight condensation apperance is okay, but puddles = head gasket)

Look at the white plastic coil pack housing that sits on top of the spark plugs for any cracks or burn marks.

For your coolant problem look for external coolant leaks.

where the head and block meet (which would be related to your performance issue)
coolant overflow tank (put a water bottle on the end of the hose to monitor any expelled fluid
water outlet and heater hose on side of engine
heater hose underneath exhaust manifold that comes from the water pump and leads to the firewall, there is a plastic connector that connects the hose to the metal tube that likes to fail

robalero · 10-09-2011, 03:47 PM

have you looked at your air filter? a clogged air filter can cause this also

Goliath · 10-09-2011, 03:55 PM

Oil on the dipstick looked great. Not milky at all. And I'll check in to the other suggestions.

I also did a little more research. It seems like a cracked vacuum line can cause this too. I looked and one of the vacuum lines (atleast I think it's a vacuum line) is dry rotting. I'll take a picture and post it just to make sure...

Goliath · 10-09-2011, 04:09 PM

This is a vacuum line, right? It looks pretty dry rotted and cracked, so I'm thinking this could be the problem.

If it is, does anyone know a part number? I can't seem to find anything...

whiterider00 · 10-09-2011, 04:10 PM

i had similar, but not as bad issues, and it was a cracked vacuum line to my MAP sensor. replaced it and the issue has seemed to stop. i have a feeling the vacuum line youre talking about is the same one.

whiterider00 · 10-09-2011, 04:11 PM

damn, beat me with the pic. ya thats the one i replaced.

Goliath · 10-09-2011, 04:14 PM

Quote:

Originally Posted by whiterider00

damn, beat me with the pic. ya thats the one i replaced.

Sweet! Were you able to find an exact replacement, or did you just use a generic hose?

zearchyo · 10-09-2011, 05:01 PM

i used a piece i found laying around but u could go to an auto parts store and ask them for a small vacuum hose/line.

[ion] C2 · 10-09-2011, 05:34 PM

Quote:

Originally Posted by Goliath

Oil on the dipstick looked great. Not milky at all. And I'll check in to the other suggestions.

So did mine the last 3 head gasket jobs. It is not a definitive test. Follow my instructions.

Quote:

Originally Posted by Goliath

Sweet! Were you able to find an exact replacement, or did you just use a generic hose?

Lol... it's a 1/4" hose for air. Go buy one from any hardware store.

whiterider00 · 10-09-2011, 06:44 PM

ya, just use some 1/4in vacuum hose. i had some laying around.

Goliath · 10-10-2011, 09:33 PM

That was the problem. Went up to autozone and got it replaced for free... lol.

I'm still planning on looking at the coil and plugs/cylinder...