1sthonda

I just got my first honda. It has 320k miles on it. I noticed that while cursing at 70 miles per hour the car will all of a sudden get a small boost in power. The RPMs will go up about 100rpm, and will want to accelerate about 1-2 mph faster. This is without me adding any pressure to the gas petal. After a few seconds it will go back to 70mph. Any ideas?

This was before I tuned it up.

I just put in a new air filter, plugs, wires, cap and rotor. However the car still does this. It also is very hesitant at low speeds. Almost like it wants to die (not sputtering or spitting, just a solid loss of power) This only lasts about a second and then accelerates normally.

Car only gets 35mpg. I thought it was supposed to get 47 plus mpg

Any info would be helpful.

Thanks!

Former User

An informative thread title is required and helps you get more responses by letting members know what specific information you need:

https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/threads-must-summarize-technical-problem-title-list-car-details-first-post-2809571/

Thread title edited.
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Have you checked the ignition timing?

Is the EGR valve and its port in the IM clogged?

1sthonda

I used some seafoam in the intake manifold according to the directions, but I don't know if that´s what you´re talking about. (a ton of smoke came out for about 20 minutes) Where is the EGR valve? I don't know how to check the ignition timing. Any suggestions?

delsolproblems

That sort of issue commonly happens when the timing is a little off, as ronjaht mentioned, when the A/F ratio is a little off, when compression is low or with a combination of these problems. At 320k I'm inclined to suggest checking your compression. Low compression could then throw the timing off as well and setting it more advanced would likely help it run better.

1sthonda

I´ll check my timing. If its low does that mean the engine needs to be rebuilt?

delsolproblems

Low compression can mean as little as a valve job or as much as all new valvetrain parts, a new or overbored block, new pistons, rings, bearings, gaskets, etc. Without a catastrophic failure like blowing a head gasket, when finding low compression at 320k miles you should expect that the engine is dying. You'd want to at least take the head off to really see how bad things are but be prepared for needing a complete rebuild or, even better for a VX, a replacement motor.

Oh, and big heavy wheels can create a similar problem, particularly with an old VX motor.

1sthonda

I wanted to take it to a tech to get the valves adjusted, but if I can find and fix it myself that would be great.

What is the compression supposed to be at? I know I can rent a tester at autozone, but I have no idea what the specs are for this kind of honda. Any ideas?

Thanks!

delsolproblems

It should be around 200 psi. You should either get a repair manual or find a good how-to for checking compression. If any valve clearances are too small, compression can suffer.

1sthonda

Thank you so much for all of your help. I´ll keep you posted and let you know what happens. I´ll get my valves worked on, compression tested, and have my timing checked.

fv8s

it "should" be around 200 psi across the board but it won't be. as long as the numbers are consistent you will be fine (as long as they aren't incredibly low)

1sthonda

Would incredibly low be under 100?

Former User

Do the compression test exactly as described at the link in my signature, and post your numbers. It's easier and faster to get good feedback with the actual numbers.

Do you have any CEL codes?

EGR valve location:



Ignition timing:

1sthonda

Compression test:

1-189psi-
2-191psi-
3-190psi-
4-193psi

That's much higher than I thought it would be. Should I still get the valves adjusted? It probably hasn't been done in a long time.

I also took off the EACV and cleaned it.


Still waiting to get the timing checked.

HatchbackSqueegee

If the car is OEM white just sell/give it to me and that will solve your problem.

1sthonda

Sorry it's OEM red. Cleaning the EAC did wonders for the car, but now It idles at about 1000rpm instead of 600-700rpm. Any ideas?

Former User

Check the timing and then do this:

1sthonda

Okay so I adjusted the idle. Seemed fine earlier today when it was warmed up. Tonight however it was back to high rpms. Upon starting the car it revs to about 1500rpm. After about 2 minutes of driving it drops to 1100rpm. The car will only go to 650-700 rpm after driving for several miles. Even then it likes to hover around a grand unless I'm at a dead stop for several seconds. Or if I turn my car off at a light and then turn it back on.

What gives? It's almost like my car thinks it's 20 degrees outside, and wants to have high RPM for way longer than it should. It was maybe about 60 degrees tonight.

Any ideas?

Thanks!

1sthonda

Okay I just realized that my cooling fan never came up when redoing the idle. My fan almost never comes on. I have only seen it come on once. And that was when I was bleeding the cooling system of air.

I know the thermostat was replaced by the 2nd owners because it was stuck in the open position. Is it possible that they replaced the thermostat they did it with one that opens at a cooler temperature? Like a 185 instead of a 195?

Or could there be another reason the fan doesn't come on?

Philtration

I was having similar racing idle, and fluctuating idle issues. I have a 1993 Civic with the 1.5L D1588 engine. I dissembled and cleaned the intake manifold and all associated valves. This cured the cars respiratory problems. There are a bunch of YouTube videos on how to disassemble and clean the manifold and associated valves.

Today with 100+ degree temperatures in Denver, the car developed a jerking issue that I have seen before when the fuel system is clogged, it actually occurred on a Buick with a fuel filter that was installed backwards. The engine is making a very VW beetle sort of sound and doesn't seem to be firing correctly. There is no smoke or evidence of incomplete combustion, just jerking while accelerating from a stop, and the idle seems lower about 250 to 400 lower than previous where it was steady at about 800-900 rpms. Any suggestions on where to start are appreciated.