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BlueOvalPower
12-23-2005, 11:47 AM
I have an off idle bog only when I hit it hard, I have a JLT CAI and Borla cat back only as of now, I know when I first got the Cobra I hit the rev limiter several times, I have read that the cats can be affected by doing this but I would assume it would do it anytime and other than off the line it runs like a champ, it doesnt look like the belt has been slipping any ideas where to look? thanks Robert

ausie
12-23-2005, 12:28 PM
I have gotten this from time to time. Usually when I am taking it easy and let the clutch out too soon (always thought it was the throw-out bearing getting stuck or squeeling) never came to think it is the supercharger belt. As far as the rev-limiter, I hit that a couple of times at the drag strip when I was not paying attention. I am not sure how that would effect the cats but I guess anything is possible. If your cats are clogged up it would smell like a skunk from what I heard.

BlueOvalPower
12-23-2005, 01:40 PM
Thanks, no skunk smell here LOL, I thought I had read that hitting the rev limiter or fuel shut off too much will crack up the honeycomb in the cats, even though the car had 4600 miles on it when purchased I don't know how the previous owner drove it, and knowing I have :), it took a little while to get the feel of the car and it will only happen if it is from a start it will get going then bog and then like slam into it like a rubber band if that makes sense, I just don't want to go to the dealer. Thanks

ausie
12-24-2005, 12:45 PM
if you are getting hesitation as you described, it may be one of several things. MAF sensor is dirty. Clean it with automotive electrical parts cleaner.
PCV valve is faulty, replace it with a new one.
Throttle plate is sticking (probable), remove the intake pipe and inspect the throttle plate for black deposits. Clean it with with throttle body cleaner (keep in mind that this stuff will remove paint so you will need a towel to catch the fluid when it flows out of the throttle body.
Last, the throttle position sensor may need replacement if it has a dead spot in it.
Finnaly, check your battery voltage. A good battery should have about 14Vdc. You can probably get the battery tested at Autozone or some car parts shops. They will do a load test on the battery, if the voltage drops too low, the battery either needs replacement or the cells are lacking proper fluid level.

I reserve my last comment with reservations....... please do not take it the wrong way.... and yes it does take a little getting used to. I used to have an 01 which is far different than the 04. All based on timming of the gas and clutch. Once in a while I get caught with my old habbits. Once you get the feel when the clutch begins to grab that would probably identify an issue with the clutch cable adjustment. If the clutch grab seems random or if you have to push it all the way to the floor just to shift gears, it may be related to the tension on the clutch cable. If you still have the stock clutch quadrant, chances are that is the problem. If you are not sure, look under the hood. The stock clutch cable has a large black plastic bushing which mounts to the firewall (location above the drivers side valve cover almost centered above the PCV valve. ) Also if you look up under the dash board right above the brake pedal, if the large arch is white plastic you still have the stock clutch quadrant. That in itself can create drivability issues since the clutch will grab inconsistantly. Pulling up on the clutch pedal is supposed to tighten the clutch cable but the stock unit tends to loose the setting and slip back down to the loose side. If the clutch cable has a metal mounting ring and is threaded, you can adjust the clutch cable tension by turning the outmost ring counter clockwise a few turns.

This one is a long shot: it could be binding in the differential and pinion gear. if the mess and backlash was not set properly (assuming there was a gear change in the rear) will cause some issues. Also if it seems like you are pulling out on ice (every thing seems fine, engine rpm and clutch engagement is perfect but nothing happens) it may be the clutches in the differential are slipping. Almost feels like you are spooling up and wham it hits hard. Normally the differential will remain locked and will take a certain amount of torque difference between the two axles to break free to transfer power to the other wheel. I can only assume that be the case and I have had that happen once in a great while. It usually follows pushing the car hard then comming to a stop and pulling out slow. May be related to heat build up in the differential. Although I have not felt it bog down when it happens probalby because I slip the clutch more than I should.

BlueOvalPower
12-24-2005, 08:46 PM
Hey Aussie thanks, I did have my friend put it on the scanner and a code that the EGR was having problems so when he checked that it is definently reading too high of voltage the part is $89 so I will try that, he said it may not be the issue but that is an inssue relating so it is a good start, battery is good, clutch is good (should replace the quadrant anyways), rear is stock maybe soon a change, hopefully this is all it is, should find out Wed when I get a chance to get that installed thanks again.


Robert

Edit: I will clean the MAF as well that is a good thought and replace the PVC too if needed I don't drive it too much so the PVC could get sticky and I am not sure how good the JLT Air Filters maybe need to replace that too thanks

ausie
12-25-2005, 01:35 PM
Robert,
This may be the longest post I ever made, sorry for the length but hopefully helpful to some extent.


It is probable that the EGR is at fault, However, the EGR is a vacuum operated component. The EGR valve will recycle exhaust gasses into the intake plenum (low pressure side prior to the rotors of the supercharger). If it is stuck open or clogged you will get a OBDII code. You should hear it click when the motor is running at idle (almost sounds like the compressor clutch kicking in on the AC). Before you end up replacing the entire EGR system, The vacuum motor which controls the EGR valve may be at fault. A simple way to check it is to run the motor at idle with the vacuum line disconnected from the EGR valve. The end that was attached to the EGR valve will suck onto your finger. The EGR system usually cycles a few times at idle at start up. IF for any reason the parts were removed previously, it is possible the electrical connector to the vacuum motor may not be connected properly. That little plastic part is not cheap either. The EGR vacuum motor is located next to the fuel rail pressure sending unit, attached to the vacuum accessory plate mounted on the supercharger on the dirvers side. It has a round cap on it (looks similar to the boost dump valve but is closer to the snout of the sc. There should be two vacuum lines connected to it and they are color coded. Red line should connect on the bottom, green line should be above it which also connects to the EGR vavle. Start with the simple then go onto the more complicated task of removal of the EGR valve. If you have checked the EGR motor restart the engine let it idle and listen for the click. The motor may need to warm up a bit. If you do not hear the EGR diaphram click at least once after the radiator fan kicks on, then it is more than likely the EGR valve issue. Also recheck the OBDII codes incase the same code pops up. If it does not, drive the car around. It may take two to three start cycles before the error codes become updated or pending. IF the error code returns time to remove the EGR. Best to at least determine if it was the EGR before the back-breaker removal. However, the EGR can be actuated by a vacuum tool or by suction of mouth with a plastic hose (not recommended to do this with the engine running :mad: ) When you remove it, inspect the pintle and port of the EGR for excess amount of carbon. Probably better to replace it than attempt to clean it but they can be cleaned out sometimes. If it looks okay more than likely it is the EGR vacuum diaphram that is damaged. Usually what kills them is excess carbon build up either from running rich or burning small amounts of oil (which usually enters throught the PCV Valve). If you suspect the Cats at fault, you can run a diagnostic with the scantool on emissions but the car has to be driven when the scan is functioning if the conditions are not met by the scanner. When you replace or re-install the EGR, use anti-sieze lubricant (same stuff you use with spark plugs) to prevent the fittings from rusting together. Once you clear the ODBII codes, recheck for other pending codes. While you are replacing the EGR ( with no back pain hopefully, its location can be tricky, had to do the same on my 01 but much easier access than on the 03/04 motors) you might as well inspect the spark plugs for contaminants. If you have more than 30k miles on them replace them. Stay with the stock heat range of plug. If you go too cold, the coil packs may not fire properly and too hot you may get pinging or flame out. I forgot to mention that the spark plugs will also cause the hesitation issues as well. There are a few good choices, autolites, NGK, Ford motorcraft (okay). I like the Denso Irridium plugs IT22 (2004 model year) or IT20 (for the 2003), Not really sure why they have different heat ranges for the 03 and 04. There may have been a change in coil pack design between the two years. The Denso's are not cheap at all. NGK and Autolites would be the best bang for the buck. Actually the Ford Motorcraft plugs I took out of my 04 looked far different than the plugs I have seen in the 01. They almost look like the NGK irridium plugs. I have yet to have to replace any parts on the 04 (except for spark plugs and the cat back, and of course the home made (did it at work) aluminum PCV canister with integrated baffle and steel PCV valve). Much of what was replaced was not needed but did it anyway.

The JLT filter should be a re-newable type. I think it is a S&B filter but the same cleaner and oil kit for K&N may be used. There may be a cleaner kit from JLT or S&B available. Let it air dry for a day or so before you coat it with oil. Ouch, forgot if you have the JLT kit that places the MAF in the Fender. Doulble check all harness connections to the MAF, that may just be part of what you are experiencing. If they are loose, and the torque of the motor moves the engine and air intake, the wires may loose connection briefly which will cause erronerous readings from the MAF. Also inspect the wire insulation for nicks or cuts. If you have the long JLT kit which is a good kit to have it may just be a loose connection. The motor will not run if the MAF becomes disconnected (I noticed that when performing a throttle body/Intake cleaning, run motor at idle and inject cleaner into throttle body which is a bit difficult with the supercharged motor compared to the N/A of the 01). Also, inspect all the clamps on the intake pipe and throttle body boot connector. Any air bypassing the MAF may cause some issues as well. You will get the same issue if there is a vacuum leak at the PCV valve elbo but it will cause more of a sputter than a bog. I had problems with the PCV valve due to vacuum leaks which is one reason I made my own so I can use a different PCV valve. If the PCV valve sticks closed, the motor will run fine but if it remains open too much air will flow into the intake through the PCV system. The result will be poor idle, and possible IAC error codes (high idle speed). If you have a vacuum lead at the PCV fitting, any unmetered air may lead to hesitation when accelerating or just cruising. More than likely you may get start up issues when the engine is hot if the PCV is leaking.

Eric.

BlueOvalPower
12-25-2005, 09:42 PM
Eric great post and info I know a lot more about old motors and that was a lot of good stuff, I really have to learn my motor I felt like a novice reading that.

Actually this was put on a snap-on scanner friends a professional mechanic we reset the code drove it, it came back he took it off and tested the piece, it was reading higher voltage than normal, I will post a pic of it lower down, he even said it may not be it but there is something wrong with that.

The car only has 7800 miles on it, I am putting denzos in along with upper and lower pulley swap, x-pipe, with the WB and I purchased the Xcal and the racer software package for the laptop so i will be able to see more of what is happening then, yes it is the long JLT and yes it is miserable LOL to work on I did ask about the MAF nothing came up with that but when I start to dig into it I will look at that as well at least clean it and recharge the filter.

I am going to print this out and take it to him see what he thinks I have always owned older cars that I worked on and need to learn my way around the actual EFI stuff, I was saying the other day this car has been a huge learning curve for me which is good thanks again

Robert

Well I have to figure out why I cannot post pics on this site but here is a auction on ebay that is similar to what he said needs replacing ( I also wasnt sure of posting a link) ebay auction # 8023954441

edit: well that got butchered LOL hope you can still read it thanks

ausie
12-26-2005, 04:18 PM
So that is what that thing is..... EGR Pressure sensor, I would have to admit, I learned something new today. Thanks! I assumed the it was attached to the EGR feed (plumbing that comes up from the headers) and is located elsewhere.

I used to have a link for all the odbII codes and what causes it, but the link no longer lives...... :( Somtimes sensors go sour. It sometimes helps if you know what may have caused it or was it just a weak part.

However, I did find this: http://www.obd-codes.com/trouble_codes/generic/p0402-exhaust-gas-recirculation-flow-egr-excessive-detected.php

The main link is: http://www.obd-codes.com/index.php
I have been looking at a few things in here since I found it. may be helpful.

I had a similar problem with my 01. At that time I did not have a scanner so I took a wild guess. However it did not bog down in the manner you described. What it did do was ping like hell which felt like it was bogging down. Total loss of power due to detonation. Once I replaced the EGR that improved performance and resuced the pinging issue since the EGR valve was functioning properly. Unfortunately that did not cure the pinging issue completely. As it turns out there was a design flaw in the 01 heads (C casting) that lead to valve overshoot of the intake air which reduced the cooling effect of the air/fuel mixture on the intake valves. To my understanding, the same heads found their way on the first 03 models. They may have changed the valve diameters and re-camed it, but they used the same casting. They since changed the head casting in early 2003.

Hopefully what you are experiencing with the bogging issue does not also mean you are getting detonation. Just as a precautionary thought, check the spark plugs for carbon deposits. Some carbon buildup is normal, but it should not be excessive. Oil entering the PCV line or through the intake side will add to the carbon build up in the combustion chamber which may lead to detonation if left to build up. I have seen and heard of seafoam which is used to clean out carbon of the combustion chamber, but not sure how usefull it would be with the supercharger on board based on its deployment into the motor. That is something I will have to look into in the near future which may be a better method than using throttle body cleaner.

Since I am not a mechanic, let me know what your friend thinks. It is always a good thing to get a second opinion. :thumbsup: Since I have the same vehicle, it is good to find things out before it happens.

Eric.

BlueOvalPower
12-28-2005, 06:32 PM
Okay here is the results the pressure switch has been replaced much improvement now it is more of a slight bog, so we put it on the O2 machine and at idle the A/F ratio is around 33-34 at about 2000 rpm's it goes to about 40 so it is really lean, the computer was reflashed this year 5-05 shortly before I purchased it, so I am unsure of where to go from here I guess I need to put the stock air intake on and take it to the dealership, unless there is other things I should look at like what has been mentioned above, I am going to try to get the x-pipe in tomorrow with the WB so I can watch it better I wish I had bought the dual WB kit, thanks again


Robert

ausie
12-29-2005, 01:40 PM
Okay here is the results the pressure switch has been replaced much improvement now it is more of a slight bog, so we put it on the O2 machine and at idle the A/F ratio is around 33-34 at about 2000 rpm's it goes to about 40 so it is really lean, the computer was reflashed this year 5-05 shortly before I purchased it, so I am unsure of where to go from here I guess I need to put the stock air intake on and take it to the dealership, unless there is other things I should look at like what has been mentioned above, I am going to try to get the x-pipe in tomorrow with the WB so I can watch it better I wish I had bought the dual WB kit, thanks again


Robert
That does not look good at all. :eek: I thought 15 to 18 was lean. It almost looks as if you have a smaller SC pully on board and the factory tune. You could always measure the SC pully it should be 3.65 inches in diameter. If it measures up, then look at the lower pully which should be 7.5 inches. I am not sure if a recalibrated MAF would cause the high numbers, my guess would be lower than expected. Something just does not seem right there.... almost as if you are loosing fuel pressure (bad filter, bad fuel regulator, clogged fuel pump that would be assuming only one is working out of the pair, or clogged injectors. The stock 03/04 injectors should be solid blue 39lb. (they should not be all black). non-stock colors: Orange would indicate 40lb, green would be the 55lb and pink is the 65lb. If you had fuel pressure issues, more than likely the Check Engine light would be on. I am surprised it was not on for the A/F numbers you found. You may want to check battery voltage. If it drops when the engine is running that will definately cause alot of problems which will effect all of the sensor voltages as well as fuel pressure. Then again, the re-flash may be sour. Before going to the dealer, I would at least check the upper and lower supercharger pully diameters. It may be possible that the code flashed into the ECU had the wrong look-up tables (non supercharged application).

BlueOvalPower
12-29-2005, 11:08 PM
I checked the pulleys are stock size what I am thinking is I had a lot of the service records except for about the last 4-6mths I think he did some pulley work and they never re-programmed it. it just had a sticker from Ford that said a reprogram had been done about a month or so prior to me purchasing it and I got it the day after he traded it in, so I have to see what the reprogram # that is on the sticker is hopefully they can explain.


BTW I have never used the seafoam on newer cars like these but I have used them on a whole bunch of older cars especially ones that have been sitting a while with questionable gas and it works great, they will smoke for about a day and clean up great, carbs start functioning good again etc., great stuff, you can put it in the gas and if you have some sludge like my 95 F150 that I think had the oil changed once or twice LOL it was so bad, it cleaned up great it had some valve ticks and rod knocks on start up and basically after about 2-3 oil changes it is gone. thanks for the replys I will let you know what I find out

Robert

ausie
01-02-2006, 11:01 AM
Did you ever get the A/F ratio corrected? Hopefully you did before modding. I only suggested the pully may be an issue if not stock but with the stock 03 program which would at least explain why such a high number, or that the flashed program was not correct from the beginning and was botched. I would definately get it tuned to be on the safe side. I have not modified mine yet since everytime I get the mod bug, something else needs repair which is typically my explorer or the house. Perhaps this year I may get some of it done. If you are thinking of porting your Eaton, perhaps these guys would be the most helpful. Not sure what happened to Apten....

http://www.stiegemeier.com/index1.html

BlueOvalPower
01-02-2006, 11:41 AM
I talked to a guy local here that does some dyno tuning and I told him about the situation and about all the parts I have with the Xcal that has the tune for this car so he suggested get everything installed and put the tune in that is for the set up, and he will dial it in, he seems to think that it was a tune that was not reprogrammed from the dealership to stock, and read over all of this as well, hes not far away so if that doesn't work I can AAA it over there. At least with the tune I can get the A/F ratio better before driving it again. Stegmier sp? port is what I have been looking at and have read some great results as well. thanks


Robert

ausie
01-03-2006, 06:44 AM
I'll buy that,,,, sounds like a plan. I would hate to see ya burn up a piston or 8 with the A/F as high as it is. If you have to use AAA call for a flat bed (or roll back) truck. I think the front end sits too low to be towed from the rear. So far that is one thing I have not needed for either the 01 or 04.... and I hope it stays that way too. :thumbsup:

RF Cobra
01-03-2006, 11:41 AM
Robert,

Hate to hear about the troubles you are having. If you do use a rollback, make sure they use the blocking they carry with them for lower vehicles and that they put it under the bottom of the ramp. It changes the angle of the ramp just enough that it keeps from damaging the black trim piece on the bottom of the front bumper. Otherwise it will scuff it up pretty bad.