Hey everyone I'm new this website. I've had problems with my 2005 Civic EX Special Edition and I've searched and searched the forums (and even google) and haven't found anyone with a similar problem. My mechanical knowledge is limited, I don't do much of anything DIY.

My car has been in and out of the shop for the past 2 months (I've only owned it for 3 months). It has 70,000 miles, its 2005 Civic EX Special Edition Coupe. 1.7L4 PFI SOHC. I bought it from someone who told me it came out of Florida (I live in NC) and it had been sitting a little while (unsure how long, but I noticed when I changed the airfilter it had pecans and leaves inside where a squirrel had probably gotten in there).

Clean title. Test drove it, it ran fine, bought it and took it home. I bought it took it to a mechanic just to look over it and he said it looked great. No rust or anything. Put full synthetic Mobil 1 oil in it, no leaks, ran perfect.

After about a month I decided to get the timing belt changed. I've always heard people suggest at 60k miles to change it (manual says 100kish, or like 4 years), so I had it done at a local reputable mechanic shop that works on Hondas. They changed the Timing Belt, Water Pump, both drive, belts, cam and crank gaskets and the tensiors. When they changed everything, they where honest and told me they accidently broke the coolant sensor and replaced it.

Took the car home, drove it for a week and drove fine, then threw a Check Engine Light. Code P303 said Cylinder 3 was misfiring. I replaced the Ignition Coil #3. Reset check engine light and car was fine for about another week. Then all the sudden it throws a bunch of check engine lights codes read all the cylinders were misfiring.

Took it to mechanic had NGK sparkplugs placed thinking that may be causing it. Check Engine Light went off and has stayed off since, but my car idles rough from a cold start up. Drove it home. For about a week it kept idling rough from a cold start, I was told to put a few hundred miles on it and it should go away.

Put some Lucas Fuel Treatment and later put Seafoam (only did gas tank) with ethanol free gas. Didn't help.

About a week after that, I noticed my temperature gauge was going haywire, reading really hot then really cold, and noticed when I turned on the A/C it only blew cold BELOW 30 mph. Took it back to same mechanic and the coolant sensor they replaced, went bad. Had coolant sensor replaced and was good for now.

Drove car for a little while, noticed it was still rough idling on start-up so I took it back to mechanic and they said my valves were off 18 thousands of an inch and max allowed is 11 thousandths of an inch. They did a valve clearance and fixed it for about a couple days.

That's been about a week and a half since valve clearance, and it's still idling rough as hell on start up, now on EVERY start up, not just cold start ups. I've noticed I was getting over 400 miles on a tank, now I'm barely breaking 300 miles a tank and my car is idling at about 1500 rpm when sitting still.

I was driving home with my family from an amusement park yesterday and with my A/C blowing fine, the temp gauge kept reading really hot, then went down to normal after driving a little longer.

So what could be wrong? It rides normal. No check engine lights now. Only rough idling on start up (bad) and my gas mileage is sucking bad. A buddy of mine (a DIYer, but not a mechanic) said it's possible either the shop messed up on my timing belt and timings off, or there could be an air bubble in my coolant line. I haven't done anything to the fuel filters or fuel injectors yet.

Besides this issue it's a great little car, and I just switched over to Honda from driving Chevys my whole life. Please try and suggest what I should have looked at next so I can make my Honda experience a better one.

Thanks in advance!!!

 

If the timing was off or the belt slipped a tooth the problem would be constant, it would run like crap at all times and the CEL would come right back after a reset.

Are you going through any coolant? With the engine cool check the radiator (not overflow), is it full?

 

Hey thanks for the reply,

I popped the cap off and it didn't look full to the top but there's some in there. The overflow looks pretty full. On a side note, I noticed if I let it sit and idle for a bit, my RPM goes from 1250 to 750 and stays there. Is this normal?

 

Could it be a headgasket issue?? I wonder if when I had my headgasket seals replaced they might have messed up?

The Coolant fans do not turn on and my overflow is all the way backed up to the top.

 

The car will idle higher (1250 sounds right) until the engine gets warmed up, then it will idle around 750, a little higher if it's cold out.

It could be a HG issue, that can cause misfires/rough idle. They are also a common problem in 7th gen Civic's (2001-2005). It's also typical for the HG to leak worse when the engine is cold, as it heats up the HG expands and fills (or lessens) the leak. The leak will get worse over time and will start leaking at all times. They also tend not to show the normal HG signs (white smoke, oil/coolant mixed, constant overheating, low compression) on these cars.

The radiator should be full to the neck. Since you have fluid in your overflow the coolant isn't returning to the radiator when the engine cools off, probably because there is air in the cooling system. This can also cause the fans to not come on when they should.

Does the car have heat when its idling?

I would pull out the spark plugs and see how they look.

I would also bleed the air out of the cooling system. Park the car on an incline or put it on jack stands so the radiator is the high point. With the engine cool take the radiator cap off and start the car. Keep the radiator full and watch for air bubbles, give it some gas every minute or so and keep an eye on the temp gauge. If it's a HG you will probably see a constant flow of air bubbles.

 

The cars heat will not work when its idling, only when I'm driving it.

What should I look for on the spark plugs? Coolant?

 

Yeah no heat at idle is a common sign for a leaking HG in 7th gen Civic's. The heater core is the high point in the system so that's where the air tends to collect. Air prevents the water from flowing properly, it also takes up space so the system may be low on coolant even though you can see fluid in the radiator.

Look for a tint the color of your coolant on the firing end of the plug. It may also appear wet, which means it's fouled, which makes the car run like crap. They may not look too bad since they are new though. Typically it will only be 1 plug so just compare the 4 plugs and see if there are any differences.

Bleed the system and see how much air comes out and how much coolant it takes.

 

Alright I'll check my plugs when I get off work. Thanks for your help man. Another quick question: Could it be possible that when I got my gasket seals changed (at the same time I got timing belt changed) that the shop didn't seal them correctly causing it to leak?

 

You don't have to pull the head off to change the timing belt so I doubt they messed with the head gasket.

Typically shops will change the valve cover seals when they do a timing belt but this would not cause your problem.

 

Thanks a lot for your help anibis, I took my civic to the same mechanic that's been doing work on it, and he changed out the headgasket and it's working fine now. It hasn't over heated at all and it doesn't idle rough on cold start up anymore either. It cost me under $600, he had the valves (or heads, I forgot what he said) resurfaced and cleaned.

I asked the mechanic if it looked like there was any obvious permanent engine damage from the couple of times it overheated, and he said it didn't appear there was any, which I'm glad.

I had bought the car from a local dealer and the guy gave me a 3 month or 3,000 mile engine and powertrain warranty on it. I went back to the dealer the day I got it fixed, and he flipped out when I even mentioned the warranty he gave me and he said "head gasket isn't covered under the warranty" and told me to sue him and locked his doors. I doubt I'm going to pursue getting money out of him, it's gonna be more work / money than it's worth even if it happens to be covered under the warranty.

So thanks again anibis for the help man, you saved me some $$$ and headache. I'd buy you a beer and a steak dinner, but I doubt you live anywhere close to me in NC lol.