99 se grandam misfire no power [Archive] - GrandAmGT.com Forum

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ugod02010
10-01-2013, 05:25 AM
Hi guys my 99 SE is giving me a hard time. I've had a check engine for a code 440. I smell fuel all the time especially when I fill more than about $15-20 in the tank. So it's leaking but not very bad. Yesterday the car started to miss really bad under load. If I just rev while in neutral or park seems to rev good but as soon as I go to drive or reverse it misses and spits and sputters really bad. I also now had code 0302 misfire cyl 2. I cleared the code to see if it moves cyl when the light comes back on because b4 I had a random misfire for a long long time but it didn't seem to make any driving issues so I wasn't worried about it. The light hasn't come back on yet tho.
I checked fuel pressure yesterday. Key on engine off I have about 40 then it bleeds down fairly quickly. While engine is at idle I have about 38-42 when I unhook the vacuum line it jumps up to around 48-50. So seems regulator is working as it should but that pressure seems low also when the keys on and engines off. Thinking pump and tank are needed any ideas?

ugod02010
10-01-2013, 05:31 AM
Also I pulled the plug for no.2 and it almost looks like its burning quite lean there's no stale fuel on it. And checked no6 I believe. (Front right) it looked the same. So I don't think I'm losing pressure thru the injectors. And when I was limping it home after work yesterday when this started the CEL was blinking. I saw that's some kind of misfire or it means something when it blinks?

sleepyalero
10-01-2013, 06:26 AM
Blinking engine light means NOT GOOD.

AaronGTR
10-01-2013, 08:29 AM
blinking MIL means severe misfire (enough to damage the catalytic convertor). You should get this fixed before driving it any more.

Your fuel pressure is definitely low. It should be 48psi at idle with the engine on and 55psi with the vacuum tube removed (same as full throttle). Key on/engine off it should come up to 48-52 psi at least and stay there for a while. The leak down should be slow. If it's fast enough to see it drop within a couple minutes, that means either your check valve is bad, or you have a leak somewhere that is bleeding off pressure. Since you said you smell fuel, that would be the first thing I'd check. There may be some other problem behind the misfire, but until you get the fuel pressure right it will be hard to trace the problem to anything else with any certainty. Depending on where the leak is, it could be a fire hazard too!

ugod02010
10-01-2013, 04:26 PM
Thanks guys. I'm almost positive it's the pump and the tank might as well change while I'm dropping it for the pump. My trans am just had the fuel pump for a few months ago felt pretty much the same. I got the light to come back in headed out now to see what codes I get this time. See if the misfire code moved or if its still in no.2 the leak is really only enough to smell the fuel since we usually never have much in it tho. Ill post up what error I get this time

bricooper78
10-01-2013, 04:33 PM
where is it leaking? have you found the wet spot ( I didn't want to type that, just for the record, but couldn't think of any other way) underneath it? I'm with Aaron, I'd find and fix that leak first, if it doesn't have enough pressure, it's entirely possible that is your problem, but it may just be spraying it out instead of needing a pump

ugod02010
10-01-2013, 04:34 PM
Random misfire code :(

ugod02010
10-01-2013, 04:35 PM
I think it's right at the seam on the center of the tank. I was thinking maybe sucking air also

bricooper78
10-01-2013, 04:42 PM
yea, if the system isn't allowing pressure to build and hold, especially under load, the engine is going to starve. that blows, i didn't realize we had metal tanks...hell my 94ish escort had a plastic tank, I figured all cars did by now

ugod02010
10-01-2013, 05:24 PM
Pulled the little heat shield where I saw it wet its not really bad but definitely moist. Do u think it could be air getting in there and effecting it. It is right at the seam. I

bricooper78
10-01-2013, 05:26 PM
The fuel system is supposed to be sealed. If it's not, that will cause issues, just like the CES light coming on when the gas cap doesn't get screwed in right lol

ugod02010
10-01-2013, 05:28 PM
Nope it's metal and like 145$ hopefully pumps okay that's another 250

bricooper78
10-01-2013, 05:29 PM
check rockauto.com I got the good pump on there for less than that IIRC

ugod02010
10-01-2013, 05:30 PM
Thanks guys!!

ugod02010
10-01-2013, 05:52 PM
Ill keep the thread updated as I go along maybe it will help someone in the future

AaronGTR
10-01-2013, 09:28 PM
Nope it's metal and like 145$ hopefully pumps okay that's another 250

That's really weird. You sure your car is a 2000? Mine is and it has a plastic tank. They switched over to plastic in 2000. Maybe you got one of the left overs they were using up.


Anyway... it's possible you have a leak at the tank somewhere, but that wouldn't explain the low fuel pressure or the pressure dropping. That would have to be pressure in the line somewhere between the fuel pump and the regulator on the end of the fuel rail. Could be a bad fuel pressure regulator as well.

bricooper78
10-02-2013, 07:11 PM
I was thinking like the pressure loss from the cap being off the tank, that's two seperate issues then huh?

AaronGTR
10-02-2013, 10:12 PM
I was thinking like the pressure loss from the cap being off the tank, that's two seperate issues then huh?

Oh yes, definitely. The inside of the tank actually has a vacuum on it (not pressure), which is used to draw fuel vapors through the EVAP system into the manifold. When the gas cap is loose, what you are losing is that vacuum.

The fuel pressure itself is only created between the pump outlet and the pressure regulator.

bricooper78
10-03-2013, 06:35 PM
Ah ha! Welp, learned my thing for the day! This is why you da man!