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Jerry996

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Posts posted by Jerry996

  1. I decided to order all the coolant hoses for my 99 C4 (got them from Pelican) as they are now getting pretty old. I stopped in at my independent shop yesterday and was told that they have done this once for another client and the labor (inclusive of a water pump R&R) was 22 hours. Anyone out there know if this is reasonable? There are a lot of hoses (and coolant vent tubes) but I'm thinking of breaking this up into smaller jobs over time if its going to cost $2K in labor to replace the coolant hoses. Any info is much appreciated, Jerry

  2. I have a 1999 Carrera 4 and need to replace my rear tires. I'm currently running Continental Contisport Contact 2's, 225-40-18 in front and 285-30-18 in the rear. Since my front tires are at about 50% and the Contisport Contact 2's are discontinued the Tire Rack recommended the Extreme Contact DW tire. The 285-30-18 tire has been on back order for several months now but the 285-35-18 is available. Is this a good choice for me or should I wait longer? I am at the wear bars on the insides of my rear tires and fear that I'm going to get into trouble on a wet day.

    Thanks for your time, Jerry

  3. I thought that I'd end this thread with the answer to what finally solved my problems. Perhaps this will help people with similar issues. The electronics in the Throttle Body turned out to be the culprit. I had changed out the MAF with no change and the dealer remapped the ECU with no change. The throttle body was cleaned thoroughly and that also rendered no change. I took it in to my independent who drove it from cold one morning and he noticed a lot of noise (loud clicking sounds) coming from the throttle body. The codes retrieved at that time were P0102, P1503 and P1506. P1503 and P1506 were not present when this issue began. I ordered a new throttle body upon the recommendation of my independent, it took about 15 minutes to install and voila. No more surging, no hesitating, no ABS/PSM lights etc. Throttle response also seems much smoother now. Hope this helps someone and thanks for all the input.

    Jerry

  4. Yes, it is a Carrera 4, so Motronic 7.2, I'm sorry if I wasn't clear enough. I swapped out the throttle body this afternoon, it took about 15 minutes and is a very straight forward swap. The gasket is also very simple to swap out. I drove the car this afternoon, it had been parked for four days and no surging or hesitation at all (first time in ages without cold start issues.) I will drive it in the AM when it will be around 45 degrees and see how it behaves but I believe the electronics (throttle jacking unit) incorporated in the throttle body was the culprit. The throttle body was actually reasonable for a porsche part, around $220. If I still have issues in the AM then I'll report back, if not, problem solved! Thanks for the input.

    Jerry

  5. I'm changing out the throttle body on my 1999 C-4 with e-gas next week and was wondering what to expect. I looked in the DIY forum and here but did not see a posting that describes it. Can I re-use the bolts? Does the ECU (DME) need to re-learn the new throttle body? Any special tools needed? I'm changing it out because its making lots of funny noises and does not behave well when cold (surging hesitating) codes are P0102, P1503 and P1506, once it warms up all is fine. Already replaced MAF with no change. Any information is much appreciated.

    Thanks, Jerry

  6. Yes, you can do it yourself.

    Why would you replace the throttle body if the codes say throttle jacking unit (which attaches to the throttle body)?

    Well I didn't know that the "throttle jacking unit" attached to the unit. thought maybe it came with the throttle body if replaced as a whole. Which is why I posted the question. All the mechanic told me was that the throttle body was extremely noisy and possibly needed to be replaced. Could the noise be from the jacking unit? Could both need replacing? Is the jacking unit serviceable? If you can send me a part number then I'll order the jacking unit and see if that does it?

    Thanks, Jerry

  7. Update: need opinions.

    The symptoms are getting more pronounced now. The surging is becoming more frequent (probably the cooler weather). Took the car to my independent to have the air bag harnesses replaced under the seats and had them diagnose my cold start/surging issues. I have new codes now, P1503 and P1506 as well as P0102. The mechanic stated that the throttle body was very noisy and most likely causing the surging and hesitating problems. He recommended the throttle body be replaced. Is that my best course of action? If I order a throttle body does that include the electronics that may or may not be causing these issues or are those transferred from the old throttle body to the new. The mechanic stated the throttle body was less than $350. This is for a 1999 C4 E-gas. Is this something I should do myself? Thanks as always for any help given.

    Jerry

  8. Hi,

    I have a 1999 C4 (E-gas) that is still exhibiting the following problems. When first started (from cold) it idles fine, after taking off it tends to bog between 2-3000 rpm's and then the ABS/PSM warning lights come on. It then tends to surge slightly, giving and releasing throttle without moving the gas pedal. Once warm (5-10 minutes, when it reaches 180) it drives perfect. Does it no longer need the MAF after its warmed up? The code it is throwing is P0102 and 5525 according to the dealer, they remapped the DME with no change. The MAF has been replaced (no change) and I believe this means it is a connection problem to the MAF. How do I test the wiring/connector to see if/where it is losing contact? Is there a fuse for the MAF? Should I be trying something else? I have cleaned the throttle body twice with no change and run nothing but premium Chevron and have run a bottle of Techron cleaner through it with no change.

    Any help is much appreciated, Jerry

  9. Well I started the car this morning and the idle seemed to be better but still hunting a bit after the air pump turned off and the idle dropped. I would say the hunting is minimal, less than before. The bad news is that it was 70 degrees here this morning and perhaps that's why it ran pretty good. It was only slightly sluggish taking off and the ABS/PSM lights did not come on. Perhaps the throttle body cleaning did the trick, will have to wait for a cooler morning to be sure. Perhaps the ECU still has some learning to do with the new MAF? I will have the dealer check codes and tell them about the surging when it goes in for its 75K maintenance. Thanks for all your help, this was my first issue so I really appreciate it.

    Jerry

  10. I have not had codes read since replacing the MAF. I simply replaced it after my tech said codes P0102 and 5525. I was hoping that the surge and hesitation would go away when the engine was cold (after replacing MAF), it did not. I just cleaned the throttle plate area and will now have to see how it behaves this evening or tomorrow morning. I thought that maybe I'd need to remove the battery power after replacing MAF (to clear ECU), I thought that I'd read that here somewhere but wasn't sure. If the surging when cold only is not the MAF then it must be something else, we'll see if the throttle body cleaning helped. I did get some residue but nothing compared to my SVO mustang but that's a different set-up with turbo charging and all.

    Thanks for all the help! Will let you know what happens when the engine's cold again.

    Jerry

    So if I understand correctly....you replaced the MAF, but did not clear the codes. You should clear the codes...if you do this via a battery reset, you will have to let the ECU re-learn. I would clear them, run the car and then read the codes again.

    I don't have any way of reading codes yet, need to invest in an OBDII reader. Are the relatively cheap ones worth buying? Amazon sent me an offer for an Equus 3030 Innova for $59.99 today. I did have the codes cleared by a shop before installing the new MAF and I did not drive it again until the MAF was installed. First time I drove it (engine cold) the ABS/PSM warning lights came on as I described in the first post. The car is due for its 75K service in about 500 miles so I'll have the dealership check the codes and see what they say if the cold driving symptoms remain after this throttle body cleaning.

  11. I have not had codes read since replacing the MAF. I simply replaced it after my tech said codes P0102 and 5525. I was hoping that the surge and hesitation would go away when the engine was cold (after replacing MAF), it did not. I just cleaned the throttle plate area and will now have to see how it behaves this evening or tomorrow morning. I thought that maybe I'd need to remove the battery power after replacing MAF (to clear ECU), I thought that I'd read that here somewhere but wasn't sure. If the surging when cold only is not the MAF then it must be something else, we'll see if the throttle body cleaning helped. I did get some residue but nothing compared to my SVO mustang but that's a different set-up with turbo charging and all.

    Thanks for all the help! Will let you know what happens when the engine's cold again.

    Jerry

  12. :welcome:

    P0102 Mass Air Flow Sensor – Below Limit

    – Open circuit

    – Short circuit to ground

    – Mass air flow sensor

    ABS Fault code 5525

    Incorrect data exchange from DME

    - clear and see if it returns

    For the surge problems try cleaning the throttle body and MAF (use only approved MAF cleaner). Covered here many times before.

    If the problem persists then you likely have a bad MAF.

    For the ABS problem - check your brake lights - do they come on? if not, then you have a bad brake light switch.

    If they do come on then I would reset the fault and see if it comes back.

    Ok, since I've already replaced the MAF, I'll clean the throttle body and see what that does. The brake lights work fine and from what I've read the ABS/PSM warning lights are somehow connected to the MAF issue. I had also read here that the MAF had little to do with idle/low rpm issues as it only came into play at higher rpm's.

    Thanks, Jerry

  13. I have a 1999, C4, manual trans. Lately the car has been surging when cold. You can hear the engine surge (minor hunting) when its idling (maybe 50-100 rpm's.) The car tends to bog after taking off and then the surging (increase and decrease in engine speed without moving the accelerator) becomes more noticeable at speed. The ABS and PSM warning lights usually come on after that, usually within 3 minutes. My independent pulled codes P0102 and 5525. I replaced the MAF (plus air filter and cleaned the airbox) with a new unit a few days ago with no change. After the car warms up 5-10 minutes, the surging stops and the car runs perfectly. The warning lights go away after re-start and symptoms stay away as long as the engine is not cold. Do I need to reset the ECU at this point (by removing power) or will the symptoms gradually go away (if it was the MAF) or do I have other issues.

    Any help is much appreciated.

    Jerry

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