Hello,

I've now Updated this thread:


After driving my Prelude for about 5 minutes or longer i will drastically lose acceleration. I can then turn my car off, then back on right away and i have almost all of my acceleration back for a short duration.

Any ideas on what is going on?

No CEL's Either. I had a code 12 for EGR sensor recently, cleaned it, haven't seen the code since.

Vehicle:

1993 Honda Prelude
2.3 SI
5 speed manual

Replaced:
Entire Exhaust,
(Exhaust pipes, catalytic converter (test pipe), Muffler, and manifold)
Spark Plugs (two times)
Spark Wires
Distributor Cap
Distributor Rotor
Distributor
Ignition Coil
Fuel Filter
Fuel Pump
Air Filter
Oxygen Sensor
TPS Sensor
Fuel Injectors
PCV Valve

Cleaned Parts:
Throttle Body
EGR


Thank you for your time!

 

Any weird noises when trying to accelerate? Any backfires or misfires?
Have you tried a compression test?

 

No backfires for sure. The car doesn't sound as great as it once had though. As for the compression test, no i have not. I'll put that on my checklist. I would hope my issue didn't lie there, but i have ordered some gaskets and i am going to set my lifters when they come in. They need to be set badly.

As for the weird noises, i know it rattles down by the exhaust. When the issue occurred to the point of non driving, it had to be towed, i used a trailer to get it home but when i was backing it off the trailer at my house, it snagged the exhaust.. and the results were NOT great. I have a brand new exhaust set coming in to fix that if there are any issues. The accelerating problem occurred before i messed the exhaust up, and i verified that the exhaust is flowing when idling but you never know, so i ordered a new Cat converter and the rest of the exhaust just in case. Other than that, no weird sounds i believe.

Thank you very much for your reply.

 

stop wasting money throwing parts at it and send it to someone for diagnostic.

 

I cant excactly have a diagnostics test run on a 93 prelude. And i have no CEL codes. My mechanic has it now, set my lifters. However theres no magic way to know whats going on. Im just replacing things it could be. Never said im trying to be cheap. Everything needs to be replaced eventually anyways. So please leave suggestions, Not nonessential comments.

 

Whoa take it easy there, shouldn't be saying that to a moderator, and a good one at that he is here to help give feedback/ideas, not hinder your diagnosis. He is just saying to really get cracking and start troubleshooting before you end up like me and throw away $ into your car. Have you checked your timing to see if it is dead on, sounds like that could be it or maybe a sensor issue. But like you said you arent throwing any CEL's so it would be tricky to identify what sensor would be bad.

 

I apologize if i came off as rude towards anyone regardless of status. I was simply stating my comment in regards to his comment. Since i cant run a diagnostics test on a 93 i just felt the comment was nonessential. However i did not specify that i had my mechanic troubleshooting things as well on his end. So i apologize again, if my comment came off as rude. My comment was directed towards the "diagnose" part solely.

As for your comment i fully appreciate it. Ill ask my mechanic tp check the timing today, i only replace the sensors myself and easier aspects of repair. I leave the more difficult procedures to my honda mechanic.

 

in regards to this comment, just because i am a moderator it doesnt mean i have to be talked to in some military proper way. ive simply seen way too many people throw money at their car to not solve anything when maybe your timing jumped.

just because you have no current lights, that does not mean a skilled technician cant figure out your problem. testing is where you save money. if, through testing, the sensors all test good, their is no need to replace them. not to mention if there was a sensor that far out of wack, it would typically throw a cel.

through the years, you tend to learn a few things. im glad you have someone looking at your car. hopefully he doesnt take you for a ride.

 

Please keep us updated on your issue to see if the timing was it or something totally different.

 

AH i see why you advised me to have it diagnosed, i mistook your comment. I've been stressed as well, i may have reacted poorly =/. However i don't mind replacing most of the parts because my prelude was sitting for over 2 years when i bought it. It wasn't running due to a disconnected ground at the time (took a while to figure out) and i had replaced the distributor as well to get it running. Hadn't replaced much actually besides some hoses that went bad.
Plus my gas mileage had been horrible so replacing some of the parts that impacted that was fantastic in my opinion.

 

My mechanic set my lifters and checked the timing during the process or after, he notified me. So not the timing. I talked to him about compression but he said the idle sounded good, so he doubted that was the issue.

What we discussed what we need to do next is, put the valve cover gaskets on as soon as they arrive, i bought them on ebay. Then fire the car up and see how she does. Then to test the temp sensor, knock sensor, and whatever other sensor may cause this issue, because those are two sensors i actually don't want to buy just for the hell of it lol. While we check those sensors we will also try to make sure there isnt a leak of any sorts.

However, it is just now past Christmas, so things will be a bit delayed with family events and work, etc. I'll keep everyone notified on what comes next.

Please leave any comments regarding what issues could be causing this so we can test to see if that is the issue. Thanks

 

This sounds like TPS or Knock Sensor problems. For the TPS, get a t-pin or a very tiny metal pin of some sort and backprobe the middle signal wire and test it. There are how-to's for how to test it. Do a search.

For knock sensor, until I got a shielded wire and wired it in my car would do the same thing as you. I was originally just using a regular 16 gauge wire with no metal shield on it, which was allowing the signal to get contaminated from radio interference. However, your problem might just be the knock sensor is bad. You can try pulling one from a junk yard if the TPS checks out.

 

Seriously doubt it's the knock sensor. It would affect performance and slow the car down to a "safe mode" but not as bad as described.

Just my experience with broken/melted knock sensors.

Checking the TPS would be a good idea as described above.

 

ya that's why I got it as plan B.

 

I appreciate everyone's feedback and suggestions

Thank you very much for the info on what steps to take to test those two sensors and for pointing me in that direction.

My gaskets arrived, so i can now install them tomorrow after having my lifters set just recently.

I'll then test those two sensors just to be safe, however i had already ordered a new tps which i have in the room with me next to the gaskets. So either way that will be replaced lol. I probably should have checked first, but i've been having this issue for over a month, and with the extra cash i have at the moment, i didn't mind buying it.

Just wanted to post an update, i'll post another one tomorrow and let everyone know what happened.

Also i enjoyed the information on what the knock sensor would cause, very enlightening.

 

You're going to have to calibrate the new TPS correctly anyhow. Remember, you can't just put it on, it has to be calibrated. Do a search for "how to calibrate tps"

 

Hey, I am a mechanic. I work mostly on preludes. Can i ask a couple questions.
1. Is this on a automatic or a manual car.
2. If you rev the car in neutral, does it seem to have good power?
3. When you put it into gear do the rpms go up, but you make no power?
4. What type of test have to ruled out?


First: I would check your fuel pressure, along with your ignition coil.
When was the last time you did a complete tune up? plugs, wires, cap, and rotor.

If your fuel pressure is looking good, then I would check for clogged injectors, or signs of running rich or lean. Pull the plugs; if they are white= lean, if they are black running ric

 

1: 5 Speed Manual.
2: As far as i can tell, it has good power in nuetral.
3: I believe the car acts as it should when i put it into gear, i noticed when the accelerating issue would occur, it was as if i couldnt get past a certain mph, at first i couldnt go faster than 60, then 50, then 40, but the speed of the vehicle would gradually rise, but if i hit a hill, i didn't have enough acceleration to maintain acceleration so the vehicles speed would lower.
4: What types of tests would you want me to test? Currently its at my mechanic who works on imports. I know when i disconnect the hose running to the fuel pressure regulator, the car has a drastic change, which indicates that it is working. Same thing with the temperature sensor. The TPS that was replaced, was the stock TPS, never had been changed.

I was having an interesting issue as i watched my mechanic try to figure it out, we had discovered while i was there. My 3rd injector was cutting out then randomly coming back on. i was like what the heck? Wasn't sure if it was the wires or the injector, that was when i got the new wires, just to make sure.

As for parts, i've just had quite a few things replaced recently:

Wires (as talked about above), ignition module, TPS, Lifters set, gaskets were replaced after lifters were set.

the plugs were white, indicating running lean, so i knew that was an issue. Had my o2 sensor replaced, map sensor, and tps replaced to hopefully fix that issue. If there's any other reasons it would be running lean let me know. It's been needing a good tune up which is why i've thrown a lot of parts into it even if it wouldnt fix the issue. Want my prelude running nicely ha..

and due to the issue with the exhaust being ripped when backed off a trailer, i actually have all the exhaust piping in my room, going to put it on myself tomorrow when my catalytic converter (test pipe actually) arrives tomorrow.

I was having this acceleration issue before my exhaust was messed up though, it's what caused me to have to use a trailer to get it home =/ then when lowering the car off the trailer it snagged something. Was a mess.

OH, while it starts when its cold (which its winter now, and been icy here) It kind of starts not so great, then sounds fine. So a bad cold start?

 

I am having this same problem with my 95. It has been sitting for about two or three months and when i went to start it, it haad a hard time starting. It took me over a day to get it started and found it running on three cylinders because a faulty spark plug. The hesitation was really bad at first through the whole rpm range along with rough idle. After driving it for about a week the hesitation only comes when the motor is cold on takeoffs after that it runs smooth. Except theres still little hesitation during WOT sometimes. Also when it does run smooth for some reason when I hit VTEC it looses power.

I am thinking even though the fuel filter is a little over a year old it may be clogged up from the time its been sitting. also thinking it might be clogged injectors not suplying the extra fuel for WOT and VTEC. SO im goin to try getting these parts fixed and let you guys know if it helps.

 

my lude backfires alot and i hear alot of clanks in the motor. iam missing quite a few of my sensors. im guessing thats related


Posted from Honda-tech.com App for Android

 

hey sorry to jump in but did ypu resolve the issue because iam experiencing the same exact thing with my lude. it starts rough every morning and wont stay on sometimes. also lags power and i hear lots of minute backfires.


Posted from Honda-tech.com App for Android

 

Sorry for the delay in commenting on my thread, was wanting a good comment to report back to everyone.

UPDATE:

Turns out not all my cylinders are staying on.. which is hard to explain. Like at times they are all firing while idling then others times they are not. Then when they are all firing, if you try to take the car for a spin its like they stop firing under the load.

Had my mechanic test my coil, turns out it wasn't operating at the correct amp voltage, forgive me if i worded that incorrectly. I then replaced it today, however... went to take the car for a spin and the prelude just would slowly accelerate, like very slowly. Got it up to 50 or so and turned it around and parked it.

Complete list of parts replaced so far (will be updating the main post after this comment)

Replaced:
Entire Exhaust,
(Exhaust pipes, catalytic converter (test pipe), Muffler, and manifold)
Spark Plugs (two times)
Spark Wires
Distributor Cap
Distributor Rotor
Ignition Coil
Fuel Filter
Air Filter
Oxygen Sensor
TPS Sensor
Fuel Injectors
Fuel Pump
PCV valve

What should i replace next... =/
I have no idea what it could be, since it's not giving a CEL code sigh..

 

chek your distributor my car was doing the same thing, slow as ****, when trying to accelerate, well the distributor was all the way Clockways, I put it rigth on the middle and got my problem FIX!N
EDITDE, turn the car on, and unbolt just a lil bit the screws for the distributor NOT ALOT, JUST WERE YOU CAN MOVE IT TO CLOCKWAYS OR THE OTHER WAY you will feel the change when moving distributor, USE A GLOVE THERE IS ENERGY POWER IN THERE, just saying I dint use a glove the first time and I learn my lesson good luck

 

Also I didnt had any CEL codes

 

When you first turn the car on, you have all the power (or most of it at least) as far as i can tell. After so long, you randomly lose all acceleration or it barely will accelerate.

THEN you can turn the car off and back on and you will have most of your power back, like its an electrical thing.

Any ideas guys?