Please help!!! power loss

I have a 1995 Honda Passport EX, It drives fine until the temperature gauge gets up to mid point. Once it warms up, it boggs down when you hit the gas. If sittin idle in the drive (in park) I can rev it slowly and it will rev to 6000 rpm fine. If I hit the gas hard though it stays between 4-5000 rpms and chuggs. It began overheating slightly so I flushed the radiator and took out the thermostat. I have also done the following;

Oil Change
Tune Up
Fuel Filter
Fuel Regulator
cat converter (main)

Please help. I do not want to spend 300 bucks for a fuel pump unless I must. Could this be an exaust leak? This has been going on for over 2 months, if indeed it were a fuel pump wouldnt it give me problems all the time.. not just when the car warms up?

Thanks in advance

Steve

Could be a bad O2 sensor.

When the engine is cold the ECM is operating in open loop mode and not receiving any inputs from the O2 sensor (or sensors... depending on the year). Since an O2 sensor doesn't really begin to fully generate a signal until it is warm (~600F) the ECM ignores it until it has reached a specified temperature. Once the engine warms up and the ECM switches over to closed loop the input from the O2 sensor is sensed and it starts affecting your engine's performance (i.e. adjusting the fuel/air mixture). This would account for your Passport running fine until it warms up.

Thanks a bunch Canucklehead; its a 1995 EX 3.2 4X4 190k

Is there a way to test an O2 sensor? Would the fuel pump go out all together or is it possible for it to act like this for the past 2 months?

Steve

Thanks a bunch Canucklehead; its a 1995 EX 3.2 4X4 190k

Is there a way to test an O2 sensor? Would the fuel pump go out all together or is it possible for it to act like this for the past 2 months?

SteveI doubt that the fuel pump has anything to do with your problem.

As far as testing an O2 sensor... if you have never replaced, or don't know the age of the one on your Passport and have 190k miles on it I would just get new one. The're only about $50 or so.

I agree with the O2's, if they are original, just get them out. I finally replaced mine at 152k, BIG difference.

Going to grab one now and try. Thanks so much. This forum is awesome!

something I forgot to mention that might be relevant... When the problem started happening about 2 months ago, I was able to shut off the key and start it back up and it would be fine for another 10 minutes or so while driving. Does this help at all? The o2 senser has to be ordered so I couldnt just pick it up.

Thanks again

Also, if that's an automatic transmission, don't be allowing it to overheat - if at all possible, as you'll cook that transmission in nothing flat.

I wonder if you have 2 different problems, I don't see how an old O2 sensor can cause an actual overheating condition; I can see it bogging it down for sure, but shouldn't cause it to overheat if all other systems are up to spec.

You mentioned flushing your radiator and a new thermostat, try getting a new radiator cap as well as making sure you wash the front of the radiator out really good - make sure you aim from the engine out to the bumper and try not to bend the fins if you use a power washer.

Check your fan clutch condition, and also, we've just finally found the reason as to why my late G-Dad's 454 Chevy truck kept overheating. We did everything, new radiator, thermostat, fan clutch, etc, and it still kept overheating - reason, auto transmission was not only REAL low on fluid, but it was real old and IT was overheating, causing the engine and the gauge to show red.

End result in that situation is not good - let's just say we're parting it out at this point.

Ramblin...

It only overheated before I replaced the thermostat, so that problem is solved. The only remaining issue I have is the way it boggs down once it warms up. The temp gauge never goes past center. But once it gets to center thats when the problems start. I also noticed that when the AC is on the belt squeels when I hit the gas sometimes.


Thanks!

I, too, would watch engine temps for awhile. Do you have the original rad? Despite regular flushes and coolant swaps I had to change mine at about 150K. Not only does the tranny not like it, but the all aluminum engine probably doesn't like it either. Good luck. Curious to hear the outcome! And is that nearly 200K on the original tranny???

Yes original tranny... but it has never given me any problems. Its an automatic and I have never had any slippage at all.

10-4; sorry, I mis-read your first post. Thought you were still having overheating issues.

In regards to that, make sure you swap out some tranny fluid as when the engine overheated, it also overheated the transmission - same radiator cools both.

Are you still on the original radiator?

As for the belt squeeking, mine usually only squeek when they are worn out.

Surferfletch and I get real curious of other owners with higher mileage on their automatics, cause we have a little research going seeing as to how long these trannies CAN last with proper care.

And it's exciting to us to hear of another with higher mileage then us still having good results with their transmission.

Ramblin...

Did you happen to see that prior post I made? About how initially when it started bogging down I could turn off the engine and right back on and the problem would go away temporarly? Does that make any sense?

Yes, it does make sense, cause you are momentarily resetting the computer. Like others have said, if your O2 is original, it's way past it's prime and it WILL cause serious bogging issues.

I know you said you had one on order, see what happens when it comes in.

While you're putting the O2 in, disconnect your battery for at least 30-45 minutes so the whole computer can reset - it'll take about 50 miles or so afterwards to see drastic results as the computer has to relearn it's settings.

Great... I get it tomorrow. So Im guessing, once the o2 is in, I just drive it for awhile? Will I notice any difference in the bogging down immediately?

you have been a great help

Will I notice any difference in the bogging down immediately?


Depends on whether or not that's truly the problem. I have no way of knowing 100%, rather just guessing.

You mentioned a tune-up, guessing that included spark plugs?

Yes it did. And plug wires. My concern is that I continue nickle and diming everything (up to over 500 bucks now) I put in the o2 sensor tomorrow and then find out its the fuel pump. Is it possible to rule out the pump? I had it hooked to a gauge and the fuel pressure was consistant at 38-40 psi which is correct.

Steve

I honestly know nothing of the fuel pump, as knocking hard on wood, I haven't had to replace mine as of yet - 157k miles.

I understand the frustration of spending money, but think of it this way, most people don't even make it to 100k miles without spending a couple grand, let-alone just $500 dollars at almost 200k miles.

My sister has an '02 Trailblazer with 100k miles or so, and they're thinking of having to trade it, the transmission is going out and requires a rebuild = $2k or so, and they still owe $11k on a truck that the KBB value states is only worth $9k in EXCELLENT condition - which it was, till the tranny started throwing a fit.

My point = they still owe $11k and they're having to pay $2k for a new tranny; I'm assuming your's is paid for at 190k miles? In which case, $500's not bad - as long as it resolves the situation, which with a new O2, sounds like it will.

But I do understand your frustration where it seems everything hits at once. In January, my Toyota p/up blew it's headgasket at 280k miles, $1300 later it's up and running, only to have my waterpump on the Rodeo go south in February, another $1200 out of pocket - and mainly the cost is nothing but labor, parts are cheap.

But, I'll admit I can do most things, but I won't mess with headgaskets, and the Rodeo's waterpump is behind the timing belt, in which all of it might as well get replaced.

I wouldnt worry about the fuel pump. They usually completely fail instead of just getting weak (it happens but rarely). Make sure the EGR valve and tubes are clean. Also make sure the pcv valve is clean and operating correctly. Other then that wait the the o2 sensor is in for a while and go from there.

Thats what Ive been told Gizmo. But.. you say to check and make sure all these valves are working. How can I tell?

Thanks