16 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHThe Hunt is Over - Purchased a '99 C4 Tip
Leading reported evidence
Check just prior
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
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0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed · Original poster
I checked just prior to writing this post, and front PSI was 8 under, rear was 6.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
While it's obvious there's a ground loop within the stereo, I have not, and will not have time till this weekend to start jacking it up and checking ground straps, etc.
Leading evidence: 'Check just prior' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check ground straps, etc' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed · Original poster
First thing I did was replace the 7yr old batt w/ a Yellow Top Optima H6.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed · Original poster
- original seats were worn and had a cut down the driver bottom left bolstering - they were replaced w/ non-heated seats.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
While it's obvious there's a ground loop within the stereo, I have not, and will not have time till this weekend to start jacking it up and checking ground straps, etc.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
Check ground straps, etc
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
While it's obvious there's a ground loop within the stereo, I have not, and will not have time till this weekend to start jacking it up and checking ground straps, etc.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
16 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261026T142254Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Figured I would start a new thread - original
here
I flew into Detroit last Saturday and drove it back without issue...except the issues I knew about. So far it's been great and this C4 is a pretty unique one by the build sheet - full leather, K3 Vesuvio Metallic, space grey leather interior and wild blue carpeting. Price was very good considering (and me being inherently impatient) - seller just started up a new dealership and was surprisingly great to deal with and was more knowledgable than most I've talked to on my hunt.
3 previous owners - all Southern California ownership, clean Carfax. 3rd owner (based on what the dealer could find) was an old couple that owned it for the last 11 years. Paint is damn near flawless and the interior is immaculate - buttons seem as if they've never been used, etc. Carfax attached.
110,4xx mi upon pickup - have put on ~500mi since Saturday.
Before I picked it up - I was aware of the following:
- original seats were worn and had a cut down the driver bottom left bolstering - they were replaced w/ non-heated seats. So no hot butt - I'm ok with that.
- pass door window drop down non-operable. Microswitch gets delivered today.
- no known documentation of IMS being done
- stereo issues - more on that below...
Other than that, videos sent before purchase, cold starts, etc. sounded and looked great, no smoking or anything, no rattles. Dealer had the car shipped from CA w/ ~108k and he himself put roughly ~2000mi on it while had it for a few weeks prior to me picking it up.
On the drive back - I noticed a few things:
- Needs an alignment/road balanced tires. Tires have good tread on them, stamped 2017, some Hankook tires.
- Accel pedal seems to stick and is not fluid in motion
- Battery voltage was around 9-11, long crank to start
- Dead center is roughly ~12:05. I chalk this up to horrible Michigan roads. Alignment/balance is no issue. No wobble, clunks, rattle or noises so I'm not too concerned about suspension components.
- Stereo is far worse than advertised, though in fairness, he did say from the start he only listens to NPR - as do I - and when you have that on, it's not noticeable.
- All front speakers, dash/door, and rear driver are pretty much toast. All foam gone, lots of rattle on any sort of bass. Again, not a deal breaker.
- Has HiFi package installed, tape/nav/6 disc in frunk.
- 6 disc cart does not eject.
- Every single 911 auto seems to do this, (996s, 997s, 991s) and I just don't know if it's normal or not. When shifting from P/R to drive, into R, or manual shifting to/from 1st it seems that the rear moves, closest thing I can think of is like a horse bucking - though not as bad
- Using the tape deck adapter to phone has a
massive
ground loop. Radio not as much, but still there. Here's where my issues start to concern me a little more...
First thing I did was replace the 7yr old batt w/ a Yellow Top Optima H6. Starts right up.
While it's obvious there's a ground loop within the stereo, I have not, and will not have time till this weekend to start jacking it up and checking ground straps, etc. But with the stereo completely off, there's a whine. I've started to search through threads and it seems it's 50/50 on trans or ground issues. Fuses are all good. Ground loop with stereo on does go with pedal position / speed but evens out on highway cruising speeds or becomes negligible.
The whining noise outside of the stereo though - it's hard to tell if it's normal C4/awd noise, tire noise, wheel bearings, alternator going out, or a ground strap issue. I checked just prior to writing this post, and front PSI was 8 under, rear was 6. I aired up to correct spec and will see here once I leave the office if that helps. I've never rode Hankook tires so...it could just be the tires? I'm going to get some videos and update the thread this weekend. It seems to be more pronounced at lower speeds/lower RPMs, once it hits 4000, all seems well...
K&N Intake came yesterday - which I installed and it's made a huge difference, sounds like it should, scoots like it should. Old air filter was also in need of replacement as is.
[Image-only post; no author-written text. Original image references:]
https://cimg7.ibsrv.net/gimg/rennlist.com-vbulletin/2000x1504/build_sheet_a6ac9dbc076d80a719dc7f85ec18228e94f1b5e8.jpg
https://cimg9.ibsrv.net/gimg/rennlist.com-vbulletin/2000x1504/intake_97579f6d2b389c0dec52639da13ad6fb4071aa87.jpg
Trans/motor mounts are always my first go-to it seems with any car I've purchased. It's on the list, but not a high priority until I sort out this ground loop/stereo/whining noise.
Welcome!
Motor mounts will take (maybe) 30 minutes to replace the first time you do them.
The next couple of times you'll drop that down to about 15 minutes.
All of your issues sound typical.
Do a search and you should find solutions for all of those in this forum.
I don't know if it's the same, but I put in a new deck and noticed a new whining noise (almost like a sound of a turbo), Pulled the deck and noticed one of the rca pins broke off in the stereo so it isn't making solid connection most of the time. I turned it off, don't need music for now. Eventually I'll pull the deck again and fix the connection. I'd rather listen to the engine myself...….LOL
Did you conduct a Pre-Purchase Inspection on the engine? If so, what is the health of the cylinder bores? Cam deviations? Check for intermix? Oil Analysis? etc. etc. etc.
Overall, beautiful car!
*queue judgement*
Nope. Nothing. Said f-it and bought a one-way flight same day and just went full send on the drive home. Being a true CA car, scouring isn't a concern in my eyes. It drives beautifully, shifts are sharp, etc. It's just some of the concerns I had mentioned in the initial post. I caked ~$3000 into my budget for IMS/RMS job at a local indie shop if needed. Brake pads, oil, filters, etc just arrived today so I'm sending off an oil analysis to Blackstone on Monday and can report back. I spent a full week discussing the car with the seller & he had sent a lot of pics and videos. I'm also no stranger to wrenching on my own cars so most things aren't an issue for me to handle. Though for once, I'd like to have a car that doesn't need an engine out service out of the gate...
As strange as it seems, the cars I do the most ****-research and inspections on always seem to have the most problems, I've purchased two cars sight unseen prior - they've been the absolute best ones to own maintenance-wise, fwiw
200 very spirited miles put on it last night on some hilly and curvy roads and all systems seem to be a-go.
Speaking of, any recommendations on a good indie shop in or around Indianapolis, IN?
IMHO, cylinder bore scoring is no respecter of any region of the country. You should watch the bore scoring series on YouTube. Very informative. It's not to alarm you, but make you a more informed owner. You should keep a close eye on intermix, bore scoring, and IMS bearing condition. Those are the top three IMHO. All the other stuff (e.g. clutch, belts, brakes, alternator, water pump, etc.) are pretty routine things. Don't get caught up on silly things that don't matter like which way to point you Porsche center caps. hahaha If you keep the car for the long haul, look for ways to keep the engine healthy.
I looked a lot into it w/ the last thread and the 997.1 - I determined it was going to be a big concern even though the dealer/PPI acted like they didn't know what that was. Regardless, yes I'm in agreement. I'll most likely do the IMS/RMS/Trans Mount and any other while-you're-in-there stuff before winter once I find a decent local shop.
RSS Motor Mounts, trans mount inserts, plugs, frunk struts and a few other small items are ordered and should be here in the next few days. Going to tackle all the initial stuff I've mentioned so far, then tackle the stereo/ground issues as they really don't bother me.
Welcome to the club! It's a good looking car. Super fun ahead. Not saying anything new here: all the knowledge about anything on these cars is here. And if you can't find it, post a note, someone has run into it. It seems like all the 996's are moving into the hands of people that like to work on cars. Good for us! And watch out for that one problem that you didn't list that all these cars have, speeding tickets.
Congrats on the car! And don't worry, for me, even with some of the weaknesses it is may favorite car and favorite sports car platform for so many reasons. Its fun, you can still work on it, and no one will get pissed at you for making it your own, Enjoy!
