cvpi misfire/bucking up

[raziullah007]

Hi. The culprit is a 1999 P71 police interceptor cruiser which i have babied for over a year now. Bought it with 30,000 miles, for $4,000 including tax tag and title from a family friend who's a fleet manager for local law enforcement. a killer deal. Well, i decided to clean the engine, which i have done before, without any problems. anyway, i cleaned the engine and after a while, it started to misfire/buck up. It was idling bad, abut i cleaned the coils and connectors and i changed all of the spark plugs to double platinum because they were due for a change anyway. My MAF had to be changed according to OBD scanner, which i did. Now, i'm stumped. Under load, at low rpm, it misfires or bucks up. It jerks for a second and then goes to overdrive to compensate for load. In other words, when it changes gears from2nd to third, it drops rpm (which it should under normal easy driving) and then bucks up. You have to step on it to let it not shudder and jerk. Now, what could it be? If you can think of anything, let me know, and tell me how y ou would fix it. I have technical capabilities and will try your way, as well as mine. YOu never know that someone else might have a better way to approach a problem. Anyway, please help me out.It's been burning gas like crazy too. I just cant figure it out. please post a reply here as well as try to e-mail me personal at [email protected]

thanks in advance for all of you help.

[reekor]

All of your C.O.P's ( coil over plug) need to be changed they are known for going bad. I have seen what you are talking about just a few months ago on a 97 cvpi. The car would buck as it was changing gears mostly under lite load going into 3rd and 4th gear. The car was also getting a misfire on cylinder 3 once or twice a month and only as the car was getting on the highway even though the owner drove the highway nightly.

As for the bad milege, this can sure add to it and did your bad MAF code go away? It's rare that the MAF needs to be changed, most of the time they just need a cleaning or MAF codes are trigger by other things such as vacuum leaks.

Originally Posted by raziullah007

Hi. The culprit is a 1999 P71 police interceptor cruiser which i have babied for over a year now. Bought it with 30,000 miles, for $4,000 including tax tag and title from a family friend who's a fleet manager for local law enforcement. a killer deal. Well, i decided to clean the engine, which i have done before, without any problems. anyway, i cleaned the engine and after a while, it started to misfire/buck up. It was idling bad, abut i cleaned the coils and connectors and i changed all of the spark plugs to double platinum because they were due for a change anyway. My MAF had to be changed according to OBD scanner, which i did. Now, i'm stumped. Under load, at low rpm, it misfires or bucks up. It jerks for a second and then goes to overdrive to compensate for load. In other words, when it changes gears from2nd to third, it drops rpm (which it should under normal easy driving) and then bucks up. You have to step on it to let it not shudder and jerk. Now, what could it be? If you can think of anything, let me know, and tell me how y ou would fix it. I have technical capabilities and will try your way, as well as mine. YOu never know that someone else might have a better way to approach a problem. Anyway, please help me out.It's been burning gas like crazy too. I just cant figure it out. please post a reply here as well as try to e-mail me personal at [email protected]

thanks in advance for all of you help.

[jdclassen]

I am having a similar problem with a 2000 CVPI, not as much bucking as a misfire and rough idle, along with the check engine light. Just changed the plugs(in the rain), and the tip of one of the boots broke off. I went ahead and got a new boot from the auto parts shop and it's still there I'm still having more problems with rough idling though, and it smooths out as the RPM gets over 1300 or so. I have not changed the C.O.P's, mainly because they are nearly $50 last I checked. I am currently on the hunt for a vaccuum leak, the old fasioned way with a can of ether, nothing so far. Is there a common place that tends to get vaccuum leaks, or is it something I just need to keep looking for.

What is the best way to look for a vaccuum leak without all the "proper" equipment to do so?
Anyone know of the best place to get C.O.P's for less than $35-40?

[reekor]

Ebay

Anyone know of the best place to get C.O.P's for less than $35-40?
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[jdclassen]

New boots on 2 of the plugs fixed the misfire. Glad it was a simple solution. I'm still looking into new Coils and I think new O2 sensors would be of help as well. I found some Coils on Ebay selling as new from a guy who bought out a small parts store. $10 Each. these are just OEM replacements.
Anyone have a favorite coil for their CVPI? Acel, Motorcraft, Jegs, MSD. Theres just too many to pick from.