Fuel/starting problems?

Hey there. So I am new to the community and am really looking forward to learning more about my E30. I am 18 and relatively new to vehicles, so please show some patience as I can only speak english in the car world...for now.

Anyways, I bought my E30 about a month ago, and ever since it has had trouble with starting. Whenever I'd turn the key to fire her up, she'd crank for a bit and start, or crank and sputter out, where it'd either die or pick itself up and then start. I've replaced the fuel pressure regulator, but that's about it. Also, irrelevant but, there is a strong smell of gasoline in the oil. My mpg has been next to crap too. Not sure what the deal is. There is no gas leaking under the car, either.

Sorry for the long post, just had to get my message out there. Hopefully someone can help point me in the right direction!

You may have bad rings you might be in a little deep my friend

Change oil

Compression test will tell if you have a piston issue

Fuel pump for hard start

After oil change drive 5 miles. Check oil

I'm thinking bad rings

Wicked Fast Entertainment

Also if you just got your hands on the car basics are in order.

Fuel filter
Air filter
Oil filter/change
Check belts
Hoses


Wicked Fast Entertainment

Thank you! I will definitely start there as soon as the nearest importer opens. And unfortunately its not the first time I heard of a piston/engine issue. Fingers crossed its just the fuel injectors

Oh and, you aren't talking bad O rings are you? Just want to clarify that. Thanks!

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No piston rings and bad fuel injections wouldnt cause gas in the oil :thumbdown: im 18 as well so i understand what bad news like that brings on :thumbdown:
Then again when the two top dogs chime in, we will have some excellent answers.

Do you have a comppression tester

Wicked Fast Entertainment

Compression test will tell whether it's rings or not.

You guys REALLY need to get a Bentley manual. It has step-by-step diagnostics for just such problems.

Another vote for the Bentley.
If you're going to drive a 22 yo car of any description, you're going to have to do most of the repair yourself.
Most shops don't/ can't fix anything that has no OBD2 port. The specialists that will repair these cars will cost you a fortune.
So, You need a Bentley manual for bedtime stories .
Your situation...Poor running.
A symptom...Neat fuel in the oil:
Possible scenarios:
1, the car is over fueling.
It is Over fueling due to a, a bad coolant temp sensor, or b, leaking injectors, or c, the computer being told that the engine is ingesting too much air.
2, the ignition system is deficient.
bad spark plugs, bad plug wires, other bad ignition component.
3, several small air leaks.
4, A combination of the above.
All this info and what to do about it for the most part is in the Bentley manual.

m

Pull the plugs in order and lay them out and snap pics, a comp test at the same time will help leagues with us diagnosing your issue.

I went to Autozone today and rented a conpression tester for 5 bucks, just waiting for my dad to bring the tools home and ill post my findings! Also this Bentley manual is a dream. Thanks for that

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Originally Posted by Beemnoob

Also, irrelevant but, there is a strong smell of gasoline in the oil. My mpg has been next to crap too.

sounds like you have injectors stuck open, or fouled plugs.

To HH when i get paid friday im hoping to get mine ordered so i can really start having fun

Wicked Fast Entertainment

I think I found the problem.

After testing the compression, i found my 4th cylinder to be the defective cylinder. It hit about 90 psi max for three trials. You could even hear it struggling to go up and down. The wet compression test assured me it is a ring issue.

Kinda bummed. I don't have near the amount of money to have this fixed. Anyone know of any cheap(er) and effective methods?

By the way, thanks everyone for the help. I think I'll still go on with cleaning the ICV and replacing fuel injectors etc. to try and get the best mpg I can.

That low cylinder could be a burned valve. I don't understand "struggling to go up and down". Worn out rings would travel more easily. If it really is dragging/grinding, stop running it, because the rings/piston are galled to the cylinder wall. Only way to know for sure is to pull off the head. It's not that bad a job. Valves can be fixed for relatively cheap, but a ruined piston and cylinder will cost way more. In that case a replacement engine would be your best option.

Start searching Pick-and-Pull junkyards for a replacement engine. You should be able to find one for around $200. Make sure they'll let you run a compression test BEFORE you buy it.

Well I'm speaking from see and hear kinda sense, not so much technically. The way my dad explained it was the piston was taking longer to go up and down due to poor compression. But nonetheless, a new motor is the next option. Are they honestly as cheap as ~$200 at a junkyard? Christmas is coming up and I have no need for anything else. I think ill go check out some junkyards this saturday and see what I can find.

Btw wickedfast, this bentley manual is a DREAM.

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the pistons travel at the same rate. the only things that cause it to travel at different rates would be bad rod bearings/journals or a warped out/ovaled wrist pin. and even then its such a short amount of time (at tdc & bdc)you cant notice it with it still in the block.

what did the pressures jump to doing the wet test?

Ahh okay! I used the sound of the engine cranking during the compression test between each cylinder and found one was noticably different, which I assume just 'took longer' to turn over. Thats how I meant that anyway.

After the wet test, the compression jumped to 160 very smoothly, which pointed me towards a ring issue. Are there any further tests to assure its the ring?

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leak down test. if you dont have a nice leak down tester, i found using a rubber air fitting (like picture below) and have someone hold that in there as you push say 40psi in the combustion chamber (has to be TDC on compression stroke). then take the oil fill cap off and if you hear air whistling, bad rings. also take the intake off, hear whistling, bad intake valve, exhaust same thing just really hard to hear.



sorry for the giant pic. google has failed me again

Oh wow! I had no idea there was a difference. Well then I suppose ill give this a go within the next week and let you know how it goes. Thank you!

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Really makes no diff, if you have 90 psi in one cyl you have a 99% chance of a bent valve.


I got $5 that says if you pull off your valve cover, you have a broken rocker arm.

This sounds like quite the ordeal. Would it just be better to buy another engine? That's sounding a lot more plausible considering money and tools I have versus what it takes to dig inside my engine

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Depends on you doing the work

Wicked Fast Entertainment

Oh I'm doing all the work on the car. Taking it into the stealership will be my last ditch effort if all else fails.
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You might price it after all you will have just as much work putting a new engine in

Wicked Fast Entertainment

doing a low end rebuild isnt bad and you can normally rent most the tools since you may only rering pistons maybe once. but if you do decide to rebuild the motor, do it right the first time. bore and hone the walls, have the crank journals checked and reground. full rebuild on the head take to a shop so they can match the valve seat to the valve face. it does get pricey but the payback is worth it.

going with a junkyard motor, while its out of the car, pull it apart and redo all the gaskets and that way you can also check the cylinder wall for wear and get an idea for how the motor was taken care of.

A good junk yard motor is a fine option. If you can't hear it running but it shows good compression that is a good starting point. Maybe remove the head, lap in the valves (DIY) but take it to a shop for a check for warp and a skim to true it up.. Welcome to our nightmares..........