Car cranks but no start - Headgasket job FAIL

[lonleydriver]

I am not a mechanic but just took on a head gasket job on my m3 the car cranks but does not start, after scanning the car I get p1250 and p0303 cylinder 3 misfire
Any advice?

[Hallatauer]

A P1250 code relates to fuel flow... could be a number of things from bad fuel pump, bad pressure regulator, level sensor, clogged filter etc. That would cause a no start issue. P0303... bad coil would be my first guess.

[Veleno]

Make sure all the coils are plugged in and the grounds are also screwed in.
Did it run before you replaced the gasket?

[lonleydriver]

thanks for the response guys so the issue was i forgot to put in f18 the fuse which solved the issue and the issue was Definity fuel,now though i have smoke coming from header ??

[Eric93se]

Did you have the head checked for cracks and decked? If not that's your problem.

Let it idle and see if the smoke stops. If its huge amounts and doesn't stop, then pull the head and do more reading to understand the common failures of these cylinder heads.

[lonleydriver]

thanks for the reply yes I had the head checked and decked. It is very little smoke but it is noticeable, I wasn't sure if the engine was over heatinging because of coolant not being completely in the system yet

[XnWarden]

It's normal for things to smoke a bit after a repair like this. Get everything cleaned up, make sure the cooling system is bled properly. Then drive it and see if you have any problems. I usually change the oil and coolant again about 500 miles after doing a head gasket just to make sure everything is as flushed out as it can be.

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[lonleydriver]

1998 m3 just finished a head gasket job, I've posted about this topic because it was my first time doing a big " job" anyways I got the car to run, theirs smoke well I saw some people saying it's just burning off whatever old oil crap. well, I add coolant OEM and distill water to a brand-new CSF radiator. everything is going fine I see smoke coming from the headers area I don't think its headers itself but that area its hard to see because everything is so crammed. turn the car off. and I check the dipstick wtf!!!! the oil is mixed with coolant and how did I know this? because it diluted af!! I do a oil change and use fcp euro oil change kit, now brand-new oil and turn the car on run for a bit turn it off checked the dip stick and same thing!!! what did I miss guys? I used VAC MOTORSPORT MLS HG 86mm - 0.120" ARP HEADSTUDS, new coolant pipe. decked the head resurface I was told it was good. what did i miss guys? im stressing.
I also did a m50 manifold swap is it possible i mixed a coolant line and oil?

[shogun]

I merged your 2 threads, better to have it all in one thread, so people know what has been done before.

[Eric93se]

What is the thickness of the HG?

Did you blow out all the hg bolt holes just before dropping the bolts in?

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If you don't know the difference between vac and coolant lines we can't help you.

[lonleydriver]

yes, 86mm - 0.120" HG. I followed a YouTube video step by step, I did everything I was suppose to do.

[Eric93se]

You got the wrong hg. Supposed to get standard thickness

.070" (1.778mm) thick, 87mm bore MLS head gasket

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Also know that ARP studs can be fake, especially when bought from eBay. So I hope you got them from a reliable dealer.

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I don't know the torquing procedure for studs so make sure you know how that varies from regular procedure.

[lonleydriver]

I bought it off VAC motorsport, I will use the size you mentioned. I had hard time finding what size I needed but thank you for your advice. The arp are from summit racing.

[Eric93se]

Follow up here when you get it going!

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Just to note, never run these engines low on coolant not even for a minute.

[spyderg0d]

Did you drain the oil before pulling the head or while the head was removed?
When the head is removed coolant that's undrained/undrainable will spill from the head down over the block into the cylinders and oil passages/oil pan. It should be in any head replace process that oil is drained after head is pulled, not before.

Useing a thicker head gasket won't result in mixed fluids. The are head studs usually come with their own torque sequence in the box, or can be found on the website, make sure you use the updated ones and not the sequence from the early 00s. 😉

Other than that. There are no vacuum lines or coolant lines that will cause oil to mix with the coolant aside from directly off the valve cover for the cvv.

Your best bet is to take it apart and inspect everything. Don't be discouraged. You're first big engine repair and the engine started and runs, which is much better than most diyers. You just missed a small detail somewhere in the process. For best engine results, I would get a stock headmaster thickness this time.

[spyderg0d]

Did you drain the oil before pulling the head or while the head was removed?
When the head is removed coolant that's undrained/undrainable will spill from the head down over the block into the cylinders and oil passages/oil pan. It should be in any head replace process that oil is drained after head is pulled, not before.

Useing a thicker head gasket won't result in mixed fluids. The are head studs usually come with their own torque sequence in the box, or can be found on the website, make sure you use the updated ones and not the sequence from the early 00s. 😉

Other than that. There are no vacuum lines or coolant lines that will cause oil to mix with the coolant aside from directly off the valve cover for the cvv.

Your best bet is to take it apart and inspect everything. Don't be discouraged. You're first big engine repair and the engine started and runs, which is much better than most diyers. You just missed a small detail somewhere in the process. For best engine results, I would get a stock headmaster thickness this time.

[pbonsalb]

Spydergod makes a good point about coolant spilling onto the open block as the head is removed. Did the OP observe this after pulling the head?

Did the OP remember to reinstall those long skinny recessed bolts at the very front of the head? Was the head pressure tested for cracks — assuming the HG was changed because it was presumed to be leaking, it is possible the head is cracked rather than that there was a bad gasket. Also beware it is possible to have a cracked block. You could crank studs down into the threaded hole with oil or coolant in the hole. Unlikely though. And bored have cracked but generally not at 86mm unless extreme boost and serious detonation (that would bend stock rods).

0.120 MLS is good for lowering compression when turbocharging a motor. With a centrifugal supercharger, I ran a 0.080and later a 0.098. With a turbo, I ran a 0.140 before building a motor with lower compression pistons.

[lonleydriver]

Update guys. IMG_1415 3.jpgIMG_1415 3.jpgIMG_1415 3.jpgIMG_1415 3.jpgIMG_1415 3.jpg

anything I should be looking for that may cause the leak? clearly their is coolant in the cylinder not sure if its because it spilled when I pulled the head off either way the is the current update

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[Eric93se]

The block does have a drain plug, its just above the forward most oxygen sensor. Which cylinders had coolant? Show good pics of the valve side of the head.

[XnWarden]

My guy you posted the same picture 10 times lol. Also you're doing it the hard way! I find it easier to undo the 6 collector bolts and pull the exhaust manifolds with the head. But that's just me.

I hope you plan on cleaning that block before reassembly. It's filthy. A dirty mating surface will cause a new gasket to leak, especially an MLS gasket.

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[spyderg0d]

Clean the block better.
Warden is right about the collector unless your useing the e90 manifod studs that have the torx ends. (An extremely awsome swap for any e36 guy that regularly mods or whatever)