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Discussion Starter · #1 ·
Hey all,

As I prefix all my posts (read: pleas for help), I am very new to working on my car and need quite a bit of explanation to get me along.

Anyway here's the newest symptom to diagnose: When the car is warm and put under load it will occasionally stutter really badly. It happens mostly when switching gears, though if I jam the gas hard it will happen too. The problem seems fairly intermittent though it does seem to get better when the car is still cold.

I did some searching on the forums and I've read that it might be my ICM or blocked EGR valve/ports. I found a DIY on the EGR ports (and i'm a bit intimated to be honest, but it doesn't look impossible). Is there a walkthrough for checking/cleaning the EGR valvue? Is there a good/easy way to test the ICM? Any walkthrough on it as well would be appreciated.

Also, which issue should I shoot at first? I had some problems a bit ago w/ the EGR valve - I disconnected the cable from it and forgot to plug it back up on an earlier issue. After getting the dummy light, I figured it out and hooked it back up. This is when the stuttering started happening so it seems to stand to reason the issue is there right? I have no lights on currently, but the car just isn't driving well at all once it's warm.

Any thoughts or help on this is appreciated (and forgive me if I respond with a dumb question).

Thanks!
-Ritter

Ps. '97 with ~180K, has a AEM CAI which I didn't install and know nothing about haha.
 

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When you say stuttering... like starving for ful? or stuttering like its losing and gaining power? Spark? Air filter clean? old gas?
 

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My vote: EGR. I always vote EGR. It's always the culprit.

Stuttering while accel: EGR
Loss of power: EGR
Funny smell in the trunk: EGR
Low tire pressure: EGR
Diabetes Type 2: EGR

:D

My car did the same thing when my EGR ports were clogged. Slight misfire which would get worse if I ran the A/C or punched the throttle while it was below 3.5k RPMs. I cleaned my EGR valve and did the EGR ports per the writeup and it solved it for me.
 

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Discussion Starter · #5 ·
When you say stuttering... like starving for ful? or stuttering like its losing and gaining power? Spark? Air filter clean? old gas?
When I say stuttering I mean it basically moves stops accelerating - the rpm needle dances between 2-3 and it just doesn't go anywhere for a few seconds - just shudders violently, then it runs just fine. It doesn't happen with an idle rev, only when I'm actually taking off/switching gears... Thought it was old gas as well, but ran it until it was low and filled up with some tasty premium. Would the air filter be causing this? Or could it be a crappy job re-attaching the CAI?


. Slight misfire which would get worse if I ran the A/C or punched the throttle while it was below 3.5k RPMs
This sounds pretty right by me - though I don't know if I'd call it "slight"- I worry about pulling out onto a barely busy road cause I get no power randomly! Think I might just do the port cleaning though - esp, if it helps me avoid diabetes! haha.
 

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Discussion Starter · #9 ·
Hmm. So before I even had a chance to look at the egr ports (still planning on making this happen) The car decided to throw a CEL. I jumpered it and it came back flashing 67. Helms says this is "Catalyst System Efficiency Below Threshold". And the troubleshooting flowchart doesn't give me too much (or maybe I'm just dense - SCS service connector? Is the the thing I'm jumpering?)

Anyone here run into this? I'm about to do some forum searching, but I figured I'd go ahead and ask...

Thanks!
-Ritter
 

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Alright i used to have this same problem and it annoyed the hell out of me, it is exactly as you described in your first post where the car stutters/bogs down when it is around 2-3k rpm and the engine is warm.

What i have done to eliminate my problem and its worked for me, was to:

> Clean EGR Valve
> Clean TB
> Removed IAB Plate
> Removed rubbish Short Ram for a CAI (Possible heat soak)
> Re-installed the front Harmonic Balancer (not sure if this is true, but its design was to counter engine vibrations, which might have caused the engine knock sensor to go whack at 2-3k rpm, hence why people who go to obd1 p28 don't have knock sensor or egr readings so they don't get hesitations.)
> Installed a new high flow cat instead of the test pipe i had before (I was told it had something to do with the o2 sensor not being able to read heat properly on the test pipe)

And after all that the car is now running perfectly and does not hesitate anymore. Hope that helps, good luck.
 

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Hmm. So before I even had a chance to look at the egr ports (still planning on making this happen) The car decided to throw a CEL. I jumpered it and it came back flashing 67. Helms says this is "Catalyst System Efficiency Below Threshold". And the troubleshooting flowchart doesn't give me too much (or maybe I'm just dense - SCS service connector? Is the the thing I'm jumpering?)

Anyone here run into this? I'm about to do some forum searching, but I figured I'd go ahead and ask...

Thanks!
-Ritter
It could be one of two things. Either A) Your catalyst efficiency is below threshold [meaning that your catalytic converter is no longer doing it's job to the satisfaction of EPA regulations or B) Your secondary O2 sensor is failing.

Ideally, both of those possibilities wouldn't be what it causing your misfire/stuttering problem. Perhaps a restricted/clogged cat. converter might.
 

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My friends em2 had this problem you descirbe once before and it ended up being that her tps was taking a caca.
 

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Discussion Starter · #13 · (Edited)
Just when you thought it couldn't get any worse...

Drove the car home today (CEL is still glaring at me sadly, but it's been running okayish). When I parked, the RPMs dropped verrry low. It started bucking like it was going to die - held on for a little while and then kicked off. I'm now officially scared to drive the thing.

I looked at the engine while it was jerking around and heard a hissing sound - found a vacuum tube that wasn't connected to anything. Looks like it broke off of something but I have no idea where... I took some pictures:

Here's the general location - passenger side - just on the other side of the battery.



The ripped looking vacuum tube and whatever it's connected to...





This is a shot of just on the the other side of the CAI - my hand is holding the ripped tube. Not sure what the hell this is - could it be where the tube is supposed to connect??



Anyway- What is this tube, what is it connected to? (second picture) and what the hell is that in the third picture? And could this have any reason for my screwy stuttering/low rpms/dying engine?

Thanks so much
-Ritter

PS - just to add to the pathetic-ness of this whole affair - i closed the hood and the honda emblem fell off. It's a damn sign.
 

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Just when you thought it couldn't get any worse...

Drove the car home today (CEL is still glaring at me sadly, but it's been running okayish). When I parked, the RPMs dropped verrry low. It started bucking like it was going to die - held on for a little while and then kicked off. I'm now officially scared to drive the thing.

I looked at the engine while it was jerking around and heard a hissing sound - found a vacuum tube that wasn't connected to anything. Looks like it broke off of something but I have no idea where... I took some pictures:

Here's the general location - passenger side - just on the other side of the battery.


That is supposed to be covered with a rubber sort of cover kind of like a condom except black. I think that is where the tranny fluid goes? ah I can't remember I need someone to enlighten me


The ripped looking vacuum tube and whatever it's connected to...





This is a shot of just on the the other side of the CAI - my hand is holding the ripped tube. Not sure what the hell this is - could it be where the tube is supposed to connect??



Anyway- What is this tube, what is it connected to? (second picture) and what the hell is that in the third picture? And could this have any reason for my screwy stuttering/low rpms/dying engine?

Thanks so much
-Ritter

PS - just to add to the pathetic-ness of this whole affair - i closed the hood and the honda emblem fell off. It's a damn sign.
The third one I think is for the tranny. It is supposed to be covered with a black sort of looking cap. It does the same job as a condom.
 

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Who ever did the CAI installation should have plugged the vacuum port up at the IM because there's no need of that intake runner controller thing. Just use a golf tee or something and plug that hose up. You should plug that vacuum hose to the tranny breather because it's still like an air leak. First thing for sure is that you better clean your EGR. Because that's the sign of clogged up in one or two ports and the rest are not. So the ones that are not clogged will get all the recycled exhaust in them so there'll be a misfire. This problem is like a possesed engine. There were people who replaced ICM, TPS, and even ECU. Also, for your cat code, take it off and see if it's all broken or not. If it's not but just dirty then you can just soak it in chroline bleach over night and rinse it out. It'll work like new again. Good luck.
 

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Discussion Starter · #16 ·
Who ever did the CAI installation should have plugged the vacuum port up at the IM because there's no need of that intake runner controller thing. Just use a golf tee or something and plug that hose up. You should plug that vacuum hose to the tranny breather because it's still like an air leak. First thing for sure is that you better clean your EGR. Because that's the sign of clogged up in one or two ports and the rest are not. So the ones that are not clogged will get all the recycled exhaust in them so there'll be a misfire. This problem is like a possesed engine. There were people who replaced ICM, TPS, and even ECU. Also, for your cat code, take it off and see if it's all broken or not. If it's not but just dirty then you can just soak it in chroline bleach over night and rinse it out. It'll work like new again. Good luck.

Thanks for this - I'll cinch the torn hose (what is the IM? Is there an acronym page somewhere? Haha - thanks for fielding stupid questions btw) Cleaning EGR will most likely have to start sometime this week (I'm betting it takes me longer than a day sadly). Also - the transmission breather - Someone noted it should be covered with a black cap... can I get this verified? Should I cap this or should it be the way it is?

As for the cat - is there any way to know if it's the cat or the o2 sensor? I'm betting there's a how to of pulling off the cat right? I'll do some searchin'.

Thank you all for the input, I love how much help this forum is.
-Ritter
 

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IM= Intake Manifold. Just put the black cap on the tranny breather. The way OBD II work is that it will try to enrich the engine a little to test the cat. It gets the response by the secondary O2 sensor. Normally, the secondary O2 should not respond at all because the cat cleans up all the dirty air already. But, if the cat failed to clean it then the secondary O2 will start responding from sniffing rich gas then that means that cat didn't do its job. First time this happens it will have a pending code(which is a soft code and it will not light the CEL). Second or third time the ECU will confirm that it's a hard code(it will light the CEL because of the hard code). If you have never replaced your O2 then it's a good time to replace both of them since they're too old already.
 

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Discussion Starter · #18 ·
IM= Intake Manifold. Just put the black cap on the tranny breather. The way OBD II work is that it will try to enrich the engine a little to test the cat. It gets the response by the secondary O2 sensor. Normally, the secondary O2 should not respond at all because the cat cleans up all the dirty air already. But, if the cat failed to clean it then the secondary O2 will start responding from sniffing rich gas then that means that cat didn't do its job. First time this happens it will have a pending code(which is a soft code and it will not light the CEL). Second or third time the ECU will confirm that it's a hard code(it will light the CEL because of the hard code). If you have never replaced your O2 then it's a good time to replace both of them since they're too old already.

Thank you for this - these kind of explanations go a long way!

Just for a fun update: Capped the vacuum leak - still not sure what sensor that was going to (picture 2? the black cap part?) and capped the transmission breather.
I have begun cleaning the egr valve and ports. Ran out of daylight before actually getting to all the ports (the two under the fuel rail pissed me off for a long time before I decided to pull of the fuel rail). The EGR valve is amazingly disgusting and the IACV gasket was pretty clogged up as well. I'm going to order in a new gasket along with picking up the new plugs tomorrow.

Any advice on cleaning the ports? I got the tip to use the MOPAR combustion cleaner - it's doing a decent job on the valve, so might as well use there too. Got a bunch of compressed air. I also picked up some pipe cleaners, but they suck - need a stiffer brush.... not sure what to do about that one yet.

Anyway - this all seems like it's going well.... anything else I should be doing now that I have all these pieces removed? A buddy of mine said something about fuel injector o-rings?

Thanks again for the help here, hopefully my car will stop acting like a bastard - I'll update when I find out!

Thanks,
-Ritter
 

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are you getting any puffs of smoke? smell your intake, does it smell like gasoline? always start with the most simplistic stuff then work your way through it, i'd check your plugs first
 
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