Poor idle - bobbing RPM's
02-08-2005, 10:08 AM
#1
Registered User
Thread Starter
Join Date: Feb 2005
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Poor idle - bobbing RPM's
Hello all.
Here is the story:
Took my 99 Accord VTEC I4 in for oil change and to replace a ball joint. While I was there, dealer replaced ignition switch (recall). About 2 weeks later, outdoor temperature dropped below 0F for about a week (live in Canada eh...). Engine light came on - car started to hesitate on acceleration quite bad.
They pulled the codes from the car and had a misfire on each cylinder and fuel mixture lean, fuel mixture rich codes. They told me the bosch platinum plugs had some issues in cold weather with vtec's and suggested distributor cap, rotor and plugs. I bought the parts, installed them and the hesitation (or stumbling) was solved. The dealer indicated that the fuel pressure regulator may need to be replaced because of the fuel mixture codes, but told me to change the plugs, etc... first to see if that solved everything. Well, the engine light went off again with the same code. I replaced the fuel pressure regulator and the new tube kit and guess what:
1) Idles terrible when warm (rpm gage is bobbing from 500 - 900). Barely audible whining noise.
2) When starting out cold, the engine runs fine. When the engine hits operating temperature, its almost like it stalls (like the mixture is waaay to rich) for a split second. Once warm, the symptom does not come back until the next day.
3) Starts fine and drives fine, problem is idling and when taking out the clutch. When driving and depressing the clutch pedal, the rpm's fall to ~200 like it is going to stall, but bobs back up to ~650 ish..... If I blip the throttle and rev the engine, when it cycles back to idle, the same thing happens - drops to ~200 and almost stalls then back to idling between 500-900.
4) After the regulator was replaced I am getting this annoying vibration from behind the engine - can hear it in the car from around the driver side on the firewall - like a dull drum roll of pastic on plastic or something.
Anyone else with a similar experience and/or solution?
Here is the story:
Took my 99 Accord VTEC I4 in for oil change and to replace a ball joint. While I was there, dealer replaced ignition switch (recall). About 2 weeks later, outdoor temperature dropped below 0F for about a week (live in Canada eh...). Engine light came on - car started to hesitate on acceleration quite bad.
They pulled the codes from the car and had a misfire on each cylinder and fuel mixture lean, fuel mixture rich codes. They told me the bosch platinum plugs had some issues in cold weather with vtec's and suggested distributor cap, rotor and plugs. I bought the parts, installed them and the hesitation (or stumbling) was solved. The dealer indicated that the fuel pressure regulator may need to be replaced because of the fuel mixture codes, but told me to change the plugs, etc... first to see if that solved everything. Well, the engine light went off again with the same code. I replaced the fuel pressure regulator and the new tube kit and guess what:
1) Idles terrible when warm (rpm gage is bobbing from 500 - 900). Barely audible whining noise.
2) When starting out cold, the engine runs fine. When the engine hits operating temperature, its almost like it stalls (like the mixture is waaay to rich) for a split second. Once warm, the symptom does not come back until the next day.
3) Starts fine and drives fine, problem is idling and when taking out the clutch. When driving and depressing the clutch pedal, the rpm's fall to ~200 like it is going to stall, but bobs back up to ~650 ish..... If I blip the throttle and rev the engine, when it cycles back to idle, the same thing happens - drops to ~200 and almost stalls then back to idling between 500-900.
4) After the regulator was replaced I am getting this annoying vibration from behind the engine - can hear it in the car from around the driver side on the firewall - like a dull drum roll of pastic on plastic or something.
Anyone else with a similar experience and/or solution?
02-08-2005, 12:28 PM
#3
#010597
Join Date: Nov 2003
Location: CT
Posts: 433
Likes: 0
Received 0 Likes
on
0 Posts
First, run standard NGK Copper plugs in your car. They are cheap and run the best. Second, unless you have a ton of miles on that car you shouldnt have had to replace the rotor and cap yet. Lastly the idle issue sounds to me like a clogged PCV valve or a malfunctioning Idle Air Control Valve (IAC).
02-08-2005, 03:59 PM
#4
Registered User
Thread Starter
Join Date: Feb 2005
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
It appears that I have solved **my** problem:
1) Cleaned the throttle body - did not fix the problem.
2) removed the fuel pressure regulator (the new one I put on). I was going to replace it with the old one.
Upon inspection, I realized that that I didnt see the O-ring on the fpr, but a plastic plug. I pulled the plug off and revealed the valve and the O-ring. Plug had no holes - it is there to protect the part while in the parts bag - DOH!! What an idiot . I pulled the plug off, replaced the regulator and voila - no hesitation, acceleration is fantastic again (cleaning throttle body didnt hurt), no hard idle, no bobbing rpm's, no funny noises .
Damn lucky I didnt burn out the fuel pump
.
The TSB for the issue is here:
http://www.hondalac.com/servic...e.pdf
You are right about the plugs. I have 174,000 km on my accord (around 105,00 miles). Gonna stick with the OEM to be safe.
I first had this problem when brand new; hesitation when reaching operating temperature), the dealer replaced the fuel injectors and it worked. When I replaced the FPR I encountered the same type of problems. It may be the solution to the problem for others also.
Thanks for the help.
1) Cleaned the throttle body - did not fix the problem.
2) removed the fuel pressure regulator (the new one I put on). I was going to replace it with the old one.
Upon inspection, I realized that that I didnt see the O-ring on the fpr, but a plastic plug. I pulled the plug off and revealed the valve and the O-ring. Plug had no holes - it is there to protect the part while in the parts bag - DOH!! What an idiot . I pulled the plug off, replaced the regulator and voila - no hesitation, acceleration is fantastic again (cleaning throttle body didnt hurt), no hard idle, no bobbing rpm's, no funny noises .
Damn lucky I didnt burn out the fuel pump
. The TSB for the issue is here:
http://www.hondalac.com/servic...e.pdf
You are right about the plugs. I have 174,000 km on my accord (around 105,00 miles). Gonna stick with the OEM to be safe.
I first had this problem when brand new; hesitation when reaching operating temperature), the dealer replaced the fuel injectors and it worked. When I replaced the FPR I encountered the same type of problems. It may be the solution to the problem for others also.
Thanks for the help.