Restoring a "barn" '91, need some friendly advice!

I spoke with the dealer earlier this morning and they are more than happy to take a look at the timing belt to verify if it's on correctly. Angus mentioned that they should check the cam timing and the mark alignments with the 4 pin punches. I'll bring the service manual just to be sure. I really hope this is the root of the problem so I can finally enjoy this car!

Once it's in tip top shop my intention is to drive it back to Vancouver (even though I'll have to put on almost double the km already on it :frown:). Shipping it out would be my last resort - I'd hate to see this car "lost" in transit!
 
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They test drove it and put about 60km out on the highway. The preliminary diagnostics for lack of power was trouble with the VTEC.

On the 30min drive back home I was thinking "gee, this car sucks! no power at all!" It sounded noisy like a 20 year old pantera (which my dad had previously owned) working really hard to get from 0-60. I now know I have a lot to look forward to once this car is fixed up!
 
Ray. I'm going to flat out tell you. DONT DRIVE THE CAR. PERIOD!

Take your time. I am thinking you are not hitting on all cylinders.
There is something very wrong if you state it takes forever to get to redline.
Seeing that this car does zero to 60 in 5 seconds flat, you sound like it's taking you 2-3times that. Wil, (Angus) knows these car's in and out. So does Chris at SOS and many other Primers. None of us want to see such a pristine car bend a valve, overheat, run lean etc etc.

Don't be in a rush. Find someone that will check fuel pressure, clean injectors, compression test, verify timing, check valve clearance and all the other suggestions. I have a feeling that if you don't stop driving it, this thread will have a terrible ending. :frown::frown::frown::frown:
 
Ok, it's safely back at the dealer and hopefully all of its the problems get sorted out. On the way to the dealer I took it easy making sure not to rev it too high. I mentioned my concerns about the timing belt to the mechanic as well as replacing the fuel filter and thermostat.

I got a Nissan Versa as a loaner and I can honestly say that even it has more power than my '91 right now :eek: Good handling too :tongue:
 
Ok they gave me an update on the status of the car.

They rechecked the timing marks with the 5mm pins and one the cams (?) or valves (?) was stuck closed while the other 5 were open. They re-did something to get that one open and that seemed to allow the engine to regain some power and fix the rough idling of the car. I never asked if they took off and re-did the timing belt.

Not all good news however; the car still isn't back to 100% power they say. Some possible problems they are looking into is a clogged exhaust (due to condensation-rust over the years), vacuum leaks, and some other one I forgot. The fuel filter and thermometer will also be changed but are lower on the priority list.
 
Ok they gave me an update on the status of the car.

They rechecked the timing marks with the 5mm pins and one the cams (?) or valves (?) was stuck closed while the other 5 were open. They re-did something to get that one open and that seemed to allow the engine to regain some power and fix the rough idling of the car. I never asked if they took off and re-did the timing belt.

Not all good news however; the car still isn't back to 100% power they say. Some possible problems they are looking into is a clogged exhaust (due to condensation-rust over the years), vacuum leaks, and some other one I forgot. The fuel filter and thermometer will also be changed but are lower on the priority list.

I think a good one will to be to ask for an explanation by email of what is wrong - then post it here so we can see it.

There are not 6 valves or 6 cams so don't really understand that explanation, if one cam was off (as we all suspected) they would have to re-do the timing belt, I only hope that a valve did not get bent.

- I sincerely hope this is not a case of them telling you that the "muffler bearings" are bad...

One of the major problems I see here is a lack of familiarity with the car - what do they have to compare it to? Pictures in a book?

I hope they can fix this for you Ray, and I really hope that there is no real damage.
 
Ok they gave me an update on the status of the car.

They rechecked the timing marks with the 5mm pins and one the cams (?) or valves (?) was stuck closed while the other 5 were open. They re-did something to get that one open and that seemed to allow the engine to regain some power and fix the rough idling of the car. I never asked if they took off and re-did the timing belt.

Not all good news however; the car still isn't back to 100% power they say. Some possible problems they are looking into is a clogged exhaust (due to condensation-rust over the years), vacuum leaks, and some other one I forgot. The fuel filter and thermometer will also be changed but are lower on the priority list.

I think a good one will to be to ask for an explanation by email of what is wrong - then post it here so we can see it.

There are not 6 valves or 6 cams so don't really understand that explanation, if one cam was off (as we all suspected) they would have to re-do the timing belt, I only hope that a valve did not get bent.

- I sincerely hope this is not a case of them telling you that the "muffler bearings" are bad...

One of the major problems I see here is a lack of familiarity with the car - what do they have to compare it to? Pictures in a book?

I hope they can fix this for you Ray, and I really hope that there is no real damage.
 
Got an update from the dealership:

0) Timing belt should be on correctly, though I haven't confirmed if they removed and re-installed it.

1) they took a look at the exhaust system and removed the muffer. They suspect condensation caused rust which caused the baffles to collapse. So after removing the muffler it seems to run better. Replace?

2) No issues with the VTEC

3) Irregular fuel pressure. Normal is supposed to be 30-46 psi, mine is reading 60 psi. There is a problem with the fuel pressure regulator. However, this part has since been discontinued though there is one available that can be shipped from the US. They can't guarantee this will restore "power" to the car, but it is an issue that needs to be addressed.
 
Got an update from the dealership:

0) Timing belt should be on correctly, though I haven't confirmed if they removed and re-installed it.

1) they took a look at the exhaust system and removed the muffer. They suspect condensation caused rust which caused the baffles to collapse. So after removing the muffler it seems to run better. Replace?

2) No issues with the VTEC

3) Irregular fuel pressure. Normal is supposed to be 30-46 psi, mine is reading 60 psi. There is a problem with the fuel pressure regulator. However, this part has since been discontinued though there is one available that can be shipped from the US. They can't guarantee this will restore "power" to the car, but it is an issue that needs to be addressed.

OK - the OEM muffler is made of stainless steel, I have yet to see a rusted one.

Fuel pressure that high could be caused by a bad reg. but I doubt you would feel much in terms of power loss.

Sounds like you are on a ride my friend, keep us posted.


P.S. - if you need a regulator, I have a couple good ones, you can have one.
 
It sounds like there is a good amount of guessing going on...

I may as well add my guess as well: If fuel pressure is too high and the car has been sitting for 15 years, the injectors are probably varnished and dripping rather than spraying. I could be wrong, but after that much time, they should probably be checked anyway. (Was the fuel filter changed?) (or did I miss that detail)

I suggest you find a way to get this car to Angus. It needs experience, and unfortunately West Side doesn't seem to have or can get the expertise required. West Side is a good shop. But experience speaks volumes when working on a car like this. Vancouver is the final destination for this car.

Ray.K: Others here have offered to talk to the dealer, is that still possible?
 
I think a good one will to be to ask for an explanation by email of what is wrong - then post it here so we can see it.

There are not 6 valves or 6 cams so don't really understand that explanation, if one cam was off (as we all suspected) they would have to re-do the timing belt, I only hope that a valve did not get bent.

- I sincerely hope this is not a case of them telling you that the "muffler bearings" are bad...

One of the major problems I see here is a lack of familiarity with the car - what do they have to compare it to? Pictures in a book?

I hope they can fix this for you Ray, and I really hope that there is no real damage.


Hence Will the reason why when I do timing belts. I always line up all my marks with the old belt on and then make marks on all cogged pulleys and 2 corresponding marks on the old timing belt and then carefully transfering those marks in the exact same place on the new belt. It may seem amateur, but I have never had a timing mark off ever using this method and I have done lots and lots of timing belts on many different cars...


I have to ask, did any one drain out ALL the old gas from the car and replace it with new gas along with some 'additives' to help clean out the old gummy deposits/residue from the old gas sitting for so long?
 
Hence Will the reason why when I do timing belts. I always line up all my marks with the old belt on and then make marks on all cogged pulleys and 2 corresponding marks on the old timing belt and then carefully transfering those marks in the exact same place on the new belt. It may seem amateur, but I have never had a timing mark off ever using this method and I have done lots and lots of timing belts on many different cars...


I have to ask, did any one drain out ALL the old gas from the car and replace it with new gas along with some 'additives' to help clean out the old gummy deposits/residue from the old gas sitting for so long?

Eddie: It is about time you chimed in on this one. Where have you been? You must be busy changing tires!!!:biggrin: The fuel was removed and replace with new, but I think the dealer has not got to the fuel filter yet. We need the OP to comment on that.
 
Something like this I would start with the basics since no one from Acura has verified if the timing marks are indeed lined up since that was the most recent work done.

I would do a compression test and a vacuum test to see if all the numbers are consistant.

If the numbers on the compression test are good and consistant.
Then proceed to vacuum test. This will let you know if there is a vacuum leak.

I know in the past when I have done timing belts on quad cam v6s. I was out about 1/2 tooth on 1 cam. The idle was smooth and to me the car accelerated and drove fine... But when the customer drove it home. He felt a definite power loss. Sure enough, I was out 1/2 tooth on 1 cam..Fixed and the car felt like it had more power.

Hence the my method of marking the old and new belt technique.


The comment of 1/6 'things' being stuck open. I can only think 1 of the valves is stuck open since each cam control 6 valves. I sure hope this isnt the case and I dont think it was the case. because if a valve was indeed stuck open for whatever reason. I believe the piston would have hit the valve and bent. Causing a valve to be open all the time and you would have a lumpy idle and loss of power all the time now
 
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I predict this thread is not going to end well.

That's why it is always recommended to use professionals that have worked on 100's of NSX's not a handful. If the Acura dealer did bend a valve, you are going to have one hell of a fight on your hands getting them to make this car 100% perfect. I'm not saying they are at fault but it seems you said early on that the car ran fine before the dealer began their work.

Again, I would not drive this car at all and tell the dealer not to call you unless the car goes 0-60 in 5 seconds! (or damn close)
 
Another update:

1) TB: Thanks to all the experience and insightful input from prime members, I brought it back to get it rechecked, and indeed it WAS off by 1 tooth. (thumbs up Warren, Redbird and Angus) The timing marks now all line up and they assured me that it is on properly now, but 100% has not yet been restored :confused::confused::confused: I'm feeling more and more uneasy by the day; I hope no permanent damage was caused driving 100km and reving up to 7000 with the TB improperly installed... I will ask about a possible bent valve.

2) Fuel pressure regulator: It will be replaced next week, which they assure me will correct the irregularly high 60psi fuel pressure. (thanks for the offer Angus but at this point I'm stuck with fixing it up here...) I asked about the fuel injectors and they said they are clean and working fine. However I'll be sure to ask this again to confirm.

3) Fuel Filter: It will be replaced within the next few days.

4) Thermostat: It will also be replaced within the few days.

They removed all the old gas and put new gas 2 weeks ago the 1st time I brought it in. I don't believe they put in any additives to clean out the old gummy deposits. I will definitely inquire about this.

I have suggested a vacuum test but I cannot confirm if they checked or not. I will ask about this and the compression test.

At this point, they are pretty much "guessing" on how to restore power to this car. The mechanic is examining everything with a fine-tooth comb I was told. They have their inside acura/honda help line which they consult when they are stumped on things, but I will see if they would be willing to talk to other experienced NSX mechanics. Much thanks again to all prime contributors. :smile:
 
Shocking that after all that they finally found a TB error.

At minimum, they owe you a compression test (read free).

That will answer your concerns re valves etc...
 
I have a boat with a 115 Suzuki 4 stroke. 10 years old and it began to run badly. I could only manage 5000 rpm's where normally it would go 6000. It was a little hard to notice becaue my boat has twins.

The first thing I did a was a compression test. 195 195 195 120:mad:

Yup, I jumped an offshore wake, the boat caught air and the props instantly ran to redline and then some. Bent a valve.

The only way to make SURE a valve is not bent or a ring stuck would be a compression and leakdown test. Also, before you leave the dealer tripple check the entire car for any little ding, dent or scratch!!!
 
A bent valve is NOT the end of the world. Don't let anyone talk you into thinking the car will never be the same again etc. I had an 11000+ RPM mis-shift at the track in my 2000 ITR (not my current R) many years ago when I missed a gear at the worst possible time. I got the clutch in but it was too late. The negative G's felt like I was going to fly through the windshield. It was embarrassing but I'm a really good driver and the people I was with knew that. They teased me relentlessly of course. Piston wasn't even scratched. Valves were destroyed on 2 cylinders and jumped a couple of teeth. Replaced, lash set to spec. Car was amazing for years after.
 
Question is though if there is a bent valve or two who should be responsible to pay for it?

I'm leaning towards West Side Acura for letting the car out of their hands with a) timing belt installed incorrectly - they should bear the responsibility of any damages that would occur for such and b) not road testing the car to make sure all issues were sorted.

Let's see what the compression and leakdown tests come back with.:rolleyes:

Side note: Ray I feel for you
 
OK finally got some good news:

1) Replaced the fuel pressure regulator and pressure is back to normal. Apparently the faulty regulator was causing the injectors to "over-inject" and thus caused the car to burn rich. He also mentioned something else heating up/overheating but now the temperature is normal. I'll ask again.

2) Replaced the spark plugs. Some weren't functioning at 100%.

3) Replaced the thermostat and fuel filter

4) Results of the compression test, 170, 165 for the rest, normal he says.

5) Vacuum test, no leaks.

He did mention needing to replace the muffler with an aftermarket one since they don't make them any more - this will improve the idle (?).

Going to pick up the car tomorrow and test it out and compare it to 1 week ago @ 50% power VS now reportedly at 100% power and "feels like it just came out of the showroom"

Fingers crossed...
 
I don't think there's a need to buy an aftermarket muffler. So many guys have put aftermarket systems on their cars that there are bound to be a bunch of perfect condition stock ones around. Post in WTB.

I know the gentleman who owns my old NSX has the OEM exhuast in a box. It was shiny and new when I sold it.
 
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