whiteyy97CL

Hey all, it's been quite a while since I've been on. My CL is displaying some strange characteristics. The most annoying one is the strange hesitation I'm having under acceleration. It is slightly noticable at various throttle percentages but becomes most apparent at full throttle. It's as if I'm trying to accelerate but the engine is failing to make power. Another detail is that when this is occurring at full throttle it smells as though the car is running very rich. I think it may be the injectors. I've done a cylinder drop test and the drop is even across all cylinders and the spark plugs, wires, distributor cap and rotor have all been changed recently as well as the fuel filter.

The idle problem is strange and intermittent as well. From time to time at idle the car will suddenly lose rpm's and stumble and then rebound as though it is dying for a split second and then recouperating.

Thank you in advance, any help, ideas or suggestions would be very, very much appreciated.

whiteyy97CL

Also pulled the spark plugs today and gapped them. The gap is fine but it appears that the car has been running lean (whitish deposits on the spark plugs). Not sure what this can mean but thought it may help anyone interested in helping me.

v-takyo!!

Does it have trouble starting up in the morning?

Myxomatosis

Can't help but mine's been doing thats stuttering crap for as long as I can remember. I usually have to hold it at 2k for 30sec or so before idling or it'll die. But the problem happens maybe once a month..
I haven't bothered fixing it, since it just seems like one of those things the dealer will take 2 days diagnosing and then give me a $1k repair option.

I think it's a sensor. However with you're other problem, I'm thinking EGR, ever get that serviced? On two previous cars I had these symptoms from a bad O2 sensor(camry and accord), so really it's almost anyones guess. Need to get the computer read.

97BlackAckCL

iTrader: (6)

remove your egr and clean it with carb cleaner

whiteyy97CL

I removed and cleaned all the EGR ports within the last 5-6,000 miles and the EGR valve and related electrical components are all new having been replaced around 10k miles ago. I noticed that the seals on my injectors are a bit wet so I think they may not be sealed. This could create a lean mixture under load as the engine sucks in air along with the fuel spray from the injectors which can create a stumbling/hesitation. I've got new seals coming in today so I'll replace those and we'll see how it goes..thanks for your input(s).

whiteyy97CL

Well I actually hooked the car up to a scan tool today and found that contrary to my opinion it's actually running rich. The computer has been trying to cut back fuel but more fuel is getting into the engine somehow. We also did a backpressure check on the exhaust and found that it is not a pugged exhaust. We also did a vacuum check on the internals and there is no internal components out of wack inside the engine. So I pulled the injectors and we pressurized the system to see if we could spot a leaky injector but couldn't find anything, nor was the fuel pressure regulator bad. And blackack we also checked the operation of the EGR valve and it is operating correctly. If we're slow tomorrow we're gonna pull it in again and look at it some more. The technician who was looking at it with the said that the timing belt may have jumped a tooth and thrown the timing off. I'm keeping my fingers crossed its something simple...

hobo2424

when you saw your injectors where they clogged? maybe getting some lucas fuel injector stuff from autozone. its only 6 bucks for the small bottle and that treats up to 25 gallons.
Good Luck.

whiteyy97CL

There was carbon deposits on the injector tips. A clogged injector would cause a lean mixture but a dirty injector could cause the solenoids to bind and stick open which would give the rich running condition we're seeing.

Today I'm gonna get it hooked back up on the scan tool to check the MAP functioning. The weird thing is that the hesitation only happens after about 1/4 throttle so if the MAP is not functioning right at this range the computer may misread TPS-MAPS input and mess with the A/F ratios. I also read that the Honda MAP sensors can be thrown off by vacuum leaks and make the car run rich so perhaps if the injector seals were creating a big enough leak it could throw the MAP off. It seemed to run great this morning after I replaced the injector seals last night. Thanks for all your advice and I'll keep you guys posted

cl-baller201

Sounds like a really technical issue.

whiteyy97CL

Funny you should say that. So far the problem seems to be fixed after I replaced all the injector seals. What I think was happening was that for some reason at about a quarter throttle the injector seals would break their seal, sucking in air along with the fuel spray. The tricky part here is that instead of leaning out the mixture as you would expect, the mixture richened which I think occurred because the MAP sensor detected the drop in manifold pressure and interpreted it as more throttle and richened up the fuel, then once this burned mixture got down to the O2 sensors the computer realized it was running too rich so it would try to cut back the fuel which gave us our -13 long term fuel trim numbers. But the ECU couldn't fix the problem because the MAP was constantly throwing it off. Thats what I think anyways cuz it seems to be fixed now after replacing those seals.

whiteyy97CL

oh and cl-baller201, your CL looks sick btw =)