Hesitation under 3k rpms...

[Pro5.0]

Hi guys,
I need some help with this one. Today my p5 started hesitating at low rpms...like it's missing power. But, when I hit 3k rpms it drives like normal and there are no issues. No check engine light either. Anyone know what could be causing this?

Thanks

The problem appears to be solved. Post #11 has my solution!

 

[Pro5.0]

Anyone??? No ideas at all?

 

[P-Funk!]

Any CEL? Is the VICS lever connected? Did the VICS plate come loose/out?

Check PCV and EGR as well. Bad/clogged injector? Run Seafoam through the tank and and suck it into the engine as well.

 

[Pro5.0]

Thanks for the reply...I just had a diagnostic run and there are a couple things wrong. The spark plugs are bad and one of the oxygen sensors is bad. I had a feeling it had to do with the exhaust....I'll let you all know if these fix it, cause I couldn't find anything about this in two days of searching online. If I can save someone else some hassle I'll feel good lol.

 

[Clarkbug]

I was having a similar problem, and just changed out all my plugs. All were out of spec on the gap, had some deposits from fuel on them. Maybe its just my imagination, but it has helped out my lower end response.

Bad 02 sensor? But no CEL or anything?

 

[tsunami7]

You need plugs, wires, and new coil boots

 

[Pro5.0]

should have clarified. It threw a CEL later yesterday, which helped. As far as wires and coils...when I buy them I only need two wires and two coil packs right? I've never worked on a car with coil packs, always had a distributor. I want to make sure I order the right parts.

Also, upon looking at the parts online...I don't find "coil packs". Is the Ignition coil the same thing? Sorry if I sound like a noob, I have just never dealt with these before, as stated above.

 

[herls]

should have clarified. It threw a CEL later yesterday, which helped. As far as wires and coils...when I buy them I only need two wires and two coil packs right? I've never worked on a car with coil packs, always had a distributor. I want to make sure I order the right parts.

Also, upon looking at the parts online...I don't find "coil packs". Is the Ignition coil the same thing? Sorry if I sound like a noob, I have just never dealt with these before, as stated above.

Same thing happened to my car, hesitation at about 3k rpms, and a week later, CEL. Was throwing the code 'too lean'.

Cleaned EGR, Replaced Spark plugs, and my Intake tube was cracked so i wrapped it in tape. Quite unsure which part fixed my issue.. Good luck.

 

[Clarkbug]

Coil Pack = ignition coil.

What did your CEL tell you? You might not need to replace all of your coils, start small (I guess cheap and easy) and work your way up. Do plugs first, see if it helps. Then go wires, then if you need to coils, then 02 sensor(s). (Unless your code said you had a bad O2 sensor to begin with, then just go there first)

herls, if you were getting a lean error, it would be your intake tube. Most likely you were sucking in air that didnt get registered by your MAF, and as a result the ECU didnt give the engine enough fuel to burn properly with the amount of air that was in the cylinder. I would suggest replacing the tube from a junker (or from one of the several for sale on the For Sale forum) rather than just tape. Otherwise you risk running lean again, and you also can suck all sorts of dirt into your engine that wont get caught in your filter.

Just my .02.

 

[Pro5.0]

Clark - the CEL told me the downstream o2 sensor was bad (CEL has gone away since then...and not returned). So that is going to be replaced. Also, it's about time for me to replace the wires, coils, and plugs. So I am just going to replace them as well. I ordered all these parts and they just got here today. I'll be installing them on Saturday.
My car has 106k miles on it, so it's due for a lot of maintenance work, including the above. Timing will need replaced and I hear it's best to have the water pump done at the same time. I don't feel like doing this myself, so a shop will have to do it in a bit.

While I'm working on it I'm going to take the door apart and figure out what is vibrating when the bass hits...this has been driving me nuts.

I'll let you all know how this goes and if it solves the issue.

 

[Pro5.0]

Solution! so far...

So to recap: Replaced the Spark plugs, Plug Wires, Ignition Coils, and Downstream oxygen Sensor. After driving over 100 miles the car drives like a new machine and there is zero hesitation. Since I needed the car to be cool while working on it I didn't get a chance to test which fixed the problem, 02 sensor or ignition, but the combination has done wonders so far. As mentioned before, I had two CEL codes which indicated the bad sensor and random misfires. In all likelihood all of these were needed. Keeping my fingers crossed.

Anyway, thanks for your help guys and hopefully if anyone else has a similar problem this thread will help them fix it quicker than I was able to.

 

[onkaimax]

So to recap: Replaced the Spark plugs, Plug Wires, Ignition Coils, and Downstream oxygen Sensor. After driving over 100 miles the car drives like a new machine and there is zero hesitation. Since I needed the car to be cool while working on it I didn't get a chance to test which fixed the problem, 02 sensor or ignition, but the combination has done wonders so far. As mentioned before, I had two CEL codes which indicated the bad sensor and random misfires. In all likelihood all of these were needed. Keeping my fingers crossed.

Anyway, thanks for your help guys and hopefully if anyone else has a similar problem this thread will help them fix it quicker than I was able to.

thanks a lot of your recap, how much does it cost you to fix all that?thanks

 

[Pro5.0]

No problem. This site has helped me immensely so I would like to extend any help to others. I found all my parts online. Compared to local parts stores and shops I saved hundreds on parts alone.

Spark Plugs (NGK V-Power) = $1.70 EA...$6.80 total
Plug Wires (NGK) = $30
Ignition Coils (Airtek) = $42 EA...$84 total
Downstream O2 sensor (Bosch Exact Fit) = $115

Grand total = $235.80 Shipping was extra.

The shop quoted me $670 installed!!! But their part cost is nearly double on most of the parts...the cost of the O2 sensor from the shop was $225 itself (almost the total of my entire order).

If you feel like going even cheaper you can get a Bosch Universal fit O2 sensor for about $70. Some say it works great, but I've heard others say it wasn't worth the hassle. I just want to install it and be done with it, so exact fit was what I wanted. Let me know if you got any questions.

EDIT: I didn't know if I could mention the online store name, but just saw a thread about it. It is www.rockauto.com . It sounds like others are very pleased with them as well.

 

[onkaimax]

thx a lot pro5.0, this forum is really good, people are nice and willing to help! thanks all!