3.4 SFI Starting slow when cold
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3.4 SFI Starting slow when cold
To keep this Fiero related, lets say I plan this for a swap :thumbleft: (actually I dont)
'Donor' car is a 1999 Grand Am SE with the 3.4L Pushrod V6. It has 250,000KM on it, and an auto. It is my girlfriends car.
Since she has had it, it would crank over for about 4-5 seconds then sputter to life whenever you let it sit for like 30 minutes or more. It would otherwise run fine, and if you let it sit for a short time, like say to fill up with gas, it would start instantly, and not sputter to life. I went to replace the plugs in it, and I only got 1 out easily, they are NGK platinum, and it had a huge gap like .090 or more, so they are past due, the other 5 are stuck. I put new plug wires on it though. I want to fix the slow starting issue, I think it is the fuel pump draining fuel back, as it seems to start better if you let the fuel pump run for the 2 seconds before cranking, but still nowhere near perfect. Also, to me the pump seems quite whiney, but it also has a metal gas tank. I had the fuel pressure checked today and it was just over 40PSI with the engine off, and held 40+ for 15 minutes after the engine shut off. Shrader valve still sprays fuel after 2 hours of sitting, but still has the long crank.
Can this be caused by the plugs or what?
EDIT: I took it on a 500KM round trip with a trunk full, and I got 34MPG with the A/C on and doing 110KM/h. No smoke is observed at startup either so I doubt a fuel injector is leaking.
'Donor' car is a 1999 Grand Am SE with the 3.4L Pushrod V6. It has 250,000KM on it, and an auto. It is my girlfriends car.
Since she has had it, it would crank over for about 4-5 seconds then sputter to life whenever you let it sit for like 30 minutes or more. It would otherwise run fine, and if you let it sit for a short time, like say to fill up with gas, it would start instantly, and not sputter to life. I went to replace the plugs in it, and I only got 1 out easily, they are NGK platinum, and it had a huge gap like .090 or more, so they are past due, the other 5 are stuck. I put new plug wires on it though. I want to fix the slow starting issue, I think it is the fuel pump draining fuel back, as it seems to start better if you let the fuel pump run for the 2 seconds before cranking, but still nowhere near perfect. Also, to me the pump seems quite whiney, but it also has a metal gas tank. I had the fuel pressure checked today and it was just over 40PSI with the engine off, and held 40+ for 15 minutes after the engine shut off. Shrader valve still sprays fuel after 2 hours of sitting, but still has the long crank.
Can this be caused by the plugs or what?
EDIT: I took it on a 500KM round trip with a trunk full, and I got 34MPG with the A/C on and doing 110KM/h. No smoke is observed at startup either so I doubt a fuel injector is leaking.
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That is the problem, I wnat to change them, but I only got 1 out, the other seem to be stuck, but I didnt really heave on them. I dont want to break a plug or strip the threads. Judging by the gap on the platinums that are in there (I got 1 out, the hardest one under the alternator on the back side), they have about 100,000-150,000Km on there, I no anitsieze.
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You CAN get old plugs out with enough patience. I've done it a few times.
Obviously, start by soaking them with penetrating oil as outlined above.
If you can get one to start, but it binds up before you turn it very far, just tighten it up again. If you work it back and forth between tight and where it binds, you'll gradually free it up and it'll go further before binding. You could spend 20 minutes working one plug this way, though.
Heat is also your friend in this case. The aluminum in the heads will expand more than the steel in the plug at a given temperature. This loosens the grip of the aluminum hole on the plug threads.
Obviously, start by soaking them with penetrating oil as outlined above.
If you can get one to start, but it binds up before you turn it very far, just tighten it up again. If you work it back and forth between tight and where it binds, you'll gradually free it up and it'll go further before binding. You could spend 20 minutes working one plug this way, though.
Heat is also your friend in this case. The aluminum in the heads will expand more than the steel in the plug at a given temperature. This loosens the grip of the aluminum hole on the plug threads.
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I dont think I can get PB Blaster in Canada, heard of it lots, never ever seen it, not even at Wal Mart, hell I just started seeing Sea Foam in stores a few years ago.
I can't soak them for a few days anyway, the car is going tomorrow, and after this weekend, it is going to get cold outside. Not one plug even budges, I have to use 2 hands on the wrench, I did not do that, but I cant budge them with 1 hand.
I can't soak them for a few days anyway, the car is going tomorrow, and after this weekend, it is going to get cold outside. Not one plug even budges, I have to use 2 hands on the wrench, I did not do that, but I cant budge them with 1 hand.
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You can get WD-40, right?befarrer wrote:I can't soak them for a few days anyway, the car is going tomorrow, and after this weekend, it is going to get cold outside. Not one plug even budges, I have to use 2 hands on the wrench, I did not do that, but I cant budge them with 1 hand.
Do you have access to the car at night? Spray a little puddle of WD around the spark plugs at night, then put the boots back on. It'll soak while the engine cools off, sit overnight and then in the morning she'll drive it away like normal. If you do this for a week or two, you should accumulate enough overnight soaks to help you break the plugs loose.
I have (carefully!) used the hot wrench to help free fasteners frozen in aluminum parts. You don't automatically lose the threads. IF the aluminum is so corroded that a hole is going to let go of its threads, there's nothing you can do about it.
Even if a hole does give up its threads, you could probably helicoil the head on the car if you fill the flutes on the STI tap with grease to catch the chips.
I told her to take it to a garage in the city. I dont live with her, she is about a 1.25 hour drive away, and you have to take the coilpacks and something else off to get to the rear plugs. I am actually more worried about the plug breaking off in the hole. Once the garage does the plugs, I will pull one and see if they put antisieze on them or not.
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will, that 086 head you sold me has a stuck plug.
I spent a half hour trying to get it out. it moves 90* and binds in either dircetion. I have PB blaster soaking it from the chamber side and I rotate the plug 90* back and forth wtching the bubbles come up as the fluid keeps penetrating the threads.
then i baked the head at 400* and brought it out. I used water to cool the plug, and still no luck.
I'm not done yet, but if this were still on the car, Id be scared.
Its sat 48 hours now with pb in the threads, we will see how it comes out tonight.
I spent a half hour trying to get it out. it moves 90* and binds in either dircetion. I have PB blaster soaking it from the chamber side and I rotate the plug 90* back and forth wtching the bubbles come up as the fluid keeps penetrating the threads.
then i baked the head at 400* and brought it out. I used water to cool the plug, and still no luck.
I'm not done yet, but if this were still on the car, Id be scared.
Its sat 48 hours now with pb in the threads, we will see how it comes out tonight.
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