jonnythan

Here's the background. 1994 Civic DX. D15B7.

Car sits for 2-3 weeks. GF starts it to back it up about 15 feet to make more parking space on the street. Works fine.

I go to start it the next day. Cranks, won't turn over.

Replaced distributor cover, rotor, and spark plugs to try to eliminate any spark issues. They were all quite old anyway and needed replacing. Same with fuel filter.

Bought an inline spark tester. All four spark plugs are firing.

Bought a fuel pressure gauge. Stuck it on the fuel filter service bolt. ~40 PSI. The spark plugs smelled like fuel when I pulled them. So far so good.

Bought a compression tester. Here's where it gets weird.

I put the compression gauge on cylinder 4 and cranked. Got something around 120 or 130 psi. Moved on to cylinder 3. Got 30 psi. "Crap, it's the head gasket" I think.

Move on to cyl 2. ~1 psi. A little tiny puff of air when I push the release valve. "Hm, gasket busted between cyl 2 and 3?"

Move to cyl 1. Same as cyl 2.

Move back to cyl 4. Still ~1 psi. Thinking my compression gauge is busted, so I put it on my car. Works fine, my Grand Am is testing out to 145 psi or so.

Back to the Honda. Thinking perhaps it's the timing belt, so I work on getting the timing belt covers off to have a look at the timing. I got the top cover off and notice there's a tiny bit of slack in the timing belt. "Ah ha." So I try to get the crankshaft pulley bolt off with an air-powered impact wrench rated at 90 psi running at 140 psi.

Sit on it for 20 minutes. It doesn't budge.

So my buddy and I think maybe we can try to eyeball the timing to see if it's off. We can move the crankshaft and we can see the piston through the spark plug hole and we can see the timing marks on the camshaft sprocket. So we get cyl 1 to be at what appears TDC and notice that the camshaft sprocket is off by 2-3 teeth from the TDC marks. So we slide the timing belt off (I imagine we shouldn't be able to do this), line up the marks, and slide it back on.

Still measuring no compression. With the valve cover off, he manually rotates the crankshaft and I observe the valves moving fully up and down in the correct order. The intake valves close with the piston at the bottom of its stroke, the exhaust valves open on the following upstroke.

So I'm totally at a loss. The engine was not starting when I know at least one cylinder was creating compression. I have not seen any cylinder create more than 20-30 psi since. I haven't heard anything that sounds like pistons breaking valves (this is an interference engine right?)

So:

Car fails to turn over. I verify spark and fuel pressure. Compression gauge shows proper compression in one cylinder, but only once and never since. An eyeball of the timing appears to be off, but only by maybe 2-3 teeth max. An eyeball "fixing" of the timing doesn't accomplish anything at all.

So.... what the hell is going on?

Thanks for any possible insights.

Boostfed86

iTrader: (1)

2-3 teeth will bend some valves, i think... try a leakdown test.

91rexhf

Check to see if the tooth on the camshaft sprocket didnt break

jonnythan

I'm going to dredge this up because it appears to have happened again.

Car sits for 2 weeks, go to start it up and it turns over but doesn't start. All 4 cylinders show spark, fuel pressure is good. At least one of the spark plugs is pretty fouled with oil after repeated attempts at starting. Compression appears low, 40-60 psi, but it's equally low on all cylinders and my gauge is a cheapie Harbor Freight that is actually pretty iffy. Cylinders appear to hold compression though.

Last time I ended up pulling the head to check for bent valves. The valves were pretty OK for a 14 year old car and didn't appear bent, but I replaced the head anyway since it was cheaper and easier than replacing the valves and getting the head surfaced. I replaced the timing belt, water pump, idler pulley, and head/intake/exhaust gaskets with it while I had it all apart. It worked fine after that.

It really strikes me that I'm facing the exact same problem as last time: car sits for 2 weeks and doesn't start, but spark and fuel are fine.

I'm really at a loss. It seems stupid to pull the head off again. Whatever the problem is it seems to be directly related to having the car sit for a couple of weeks.

So what could possibly happen over the course of sitting in a parking lot for 2 weeks that would cause this no-start?

Former User

Maybe the low compression is telling you that the cylinders are flooded with gas.

Are you burning a lot of oil? Maybe the engine doesn't start after sitting because the plugs are fouled?

jonnythan

Could the cylinders flood while the car is just sitting around? If that's all that the problem is, does it make sense that i might be able to just replace the plugs and... siphon the cylinders out or something?

The engine loses a little bit of oil. Generally a quart or less between changes. I think it leaks more than burns though.

Former User

My thinking was that the plugs are fouling due to oil burning, running rich, etc. and, after sitting for a while, the fouled plugs are preventing the engine from starting immediately, thereby flooding the engine. The engine might also be difficult to start due to ignition system problems. When were the plugs, wires, cap, and rotor last replaced? How old are the distributor, coil, and igniter unit?

jonnythan

The plugs, wires, distributor, and rotor were replaced last October.

If the engine is flooded, do I need to do anything about that in particular besides just wait? Does it make sense to let it sit for a while, then replace the plugs?

Former User

In most cases, letting the cylinders dry out is sufficient. You can do this by pulling the plugs. If the engine is heavily flooded, you may need to replace the engine oil.

Post clear pictures of the plugs. If they look fouled, replace them to see whether the engine starting problem goes away.

jonnythan

How would flooded cylinders lead to low compression?

Former User

A thin layer of oil coating your cylinders works in conjunction with the piston rings to maintain high cylinder compression. Having too much gas in a flooded cylinder thins or dilutes this important layer of oil, thereby reducing compression. If flooding is severe enough, the gas also may enter the crankcase and thin the engine oil.

jonnythan

These are copper plugs installed last fall. The last picture is from cylinder 3 and the top portion (the insulator, out of cylinder part) of it had a pretty good coating of engine oil.

I took the old plugs out about half an hour ago and it's just sitting there right now. I bought some new Bosch platinum plugs but haven't put them in yet...

jonnythan

Should I put a few drops of engine oil in the cylinders before I put the new plugs in?

jonnythan

I just put the new spark plugs in and no change

g230sport

i have a feeling its rings... lol.

nobody has mentioned rings...

could your gf have gone out on a crucial test drive overheated it like a ****, and parked it/ cooked it.

my old z6 cooked itself when i hose ruptured(no temp guage ftw... sike)

your rings could also be washed out from all of the fuel, which i believe would cause low compression seeing that the rings are junk after that...

maybe fuel injectors stuck open, which fills the cyls up with fuel while it sits?

im just throwing things that come to mind out there...

jonnythan

"Test drive"?

No. It hadn't been started in 12 days.

I took a peek in the cylinders with a flashlight and didn't see any pooled liquid. Can't see much in there, and the cylinders sit at an angle, though.

The thing is that I have the same symptoms as last time. It actually seemed like it wanted to catch a bit at first, but now it just cranks.

Maybe tomorrow when I get home I'll take the plugs out, put a little bulb pump with tube down into the cylinders to make sure there's nothing sitting in there, then add a few drops of oil to each cylinder, put the plugs back in, and have a go at it.

The only thing that seems plausible so far is some leaking fuel stripping the oil from the cylinders over the course of a few days or a week causing low compression and no start. Does that even make sense?

jonnythan

I don't like to bump, but any other comments? I'm sure the answer has to be something relatively simple.

Former User

I think the oil on the Cyl #3 plug may be due to a leaky spark plug seal in the valve cover. That's pretty easy to replace.

For the starting problem, it's best now to go back to the fundamentals.

1) Click the spark link below and use the method there to test for spark at each plug. Spark should be bright white.

Spark

2) If spark is fine, then check the mechanical timing to ensure that the cam and crank are still perfectly synchronized at TDC1. Note that the crank pulley must only be turned counterclockwise. See diagram below.

3) If the mechanical timing is fine, then click the compression link below to see whether you are doing your compression test the same way. If not, repeat the test with and without addition of 1 tablespoon of engine oil per cylinder. Your ECU fuse is Fuse #24 under the dash. Post the values.

Compression

jonnythan

Excellent. Thanks a lot. I will check those things out.

sc300508

If your timming not skip ,try to do the leak down test, i think is an piston most of time.

jonnythan

OK, I took out the spark plugs and the ECU fuse, then hooked up the compression gauge to each cylinder. They all recorded between 0 and 10 psi. I got up to about 90 out of at least one after I added some 5W-30. Then I added some oil to each cylinder, put the spark plugs back in, and tried to start it and it caught a little bit before dying again.

I guess the rings are probably shot? But when the gauge reads pressure, the pressure doesn't drop at all if I just sit there with it, which indicates to me that the rings are probably OK?

Anything I could maybe try besides pouring a thicker oil in the cylinders?

jonnythan

Any other comments?

jonnythan

I popped the valve cover off and the timing belt still looks great and is nice and tight. I'm charging the battery right now and will put some 15W-40 in the spark plugs holes tomorrow and try again...

jonnythan

So I put the new battery in, poured a little bit of 15W-40 into each cylinder, sprayed some starting fluid into the intake, and tried to start it up. Chugged a little bit, but then nothing. And a lot more nothing. Waited 10 minutes, tried again. Nothing.

Went back the next morning and just turned the key again. Coughed a bit. Opened the throttle, kept trying to start.... and it started! Puffed lots and lots of smoke, but it ran smoothly. Took it around the block and the smoke is almost gone.. I will take it for a longer drive tomorrow and hope it goes away completely. Let it sit all day and tried to start it when I got home and it fired right up no problem.

I still have no idea what the heck the problem is/may have been. I'd love to hear some theories even though it's working at the moment.

William Ga

In all likelihood you have injectors that are leaking fuel into the cylinders after the vehicle is shut off. This causes ring wash and will kill compression. I would consider replacing the injectors. I have seen this many times as a technician with many years experience.
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