Things going bump in my engine

[pvt num 11]

It's been like this since I bought it - I get on the gas pretty hard, and I get to around 2600 RPM, and then the car feels like it's retarding timing and it loses some guts. If I stay on the gas, it goes POP and resumes running. So, I have yet to experience the joys of a WOT blast down soem nice long stretch of road, and I've never seen the boost gauge above 10 PSI. Some times it does it, some times it doesn't, but I don't take my chances. Sort of annoying when I want to pass a slow Corvette on the freeway, you know...? I'm using premium fuel, but I don't have a scanmaster so I don't know my knock counts, but I'm thinking they're getting pretty high when I get on the gas. Should I run top-end cleaner through my engine to see if that helps (or just becasue it's just a good idea to do that anyway)?

 

[Lee_Burough]

Contact one of the GN owners in your locale....They post on this board all the time. Look Here to contanct them.

You must hook up a scan tool to see what is happening when you hear the problem. Don't put boost to the engine until you can use the scan tool. Even then, you need to be very conservative.

Some of the other Hawaii guys will surely help you troubleshoot your issues. Your problem could be as simple as plugs, plug wires, engine grounds, coil, ignition, poor fuel, or bad MAF....

good luck

 

[Razor]

I'm using premium fuel, but I don't have a scanmaster so I don't know my knock counts, but I'm thinking they're getting pretty high when I get on the gas. Should I run top-end cleaner through my engine to see if that helps (or just becasue it's just a good idea to do that anyway)?

You need to have someone experienced look at the car, else buy the appropriate scan tool and diagnose your issues. If the car is seeing knock... your hurting the motor.

So.. buy a scanmaster and start collecting data.. or take car to someone knowledgeable. cars cannot be repaired over the internet without some form of data. Data which may/maynot be available to the scanmaster, but at least its a start. That is unless you like throwing a lot of parts at the issue.

I looked at it this way. Dealer here wants 75.00 per hour to look at car. I decided to buy scanmaster and the money it cost me, withing a few issues.. has paid for itself.

No I dont think your issue is remedied by using top engine cleaner.

 

[pvt num 11]

Okay, so a scanning tool is in the plans. I've been driving it pretty gently, as of late. (Crosses fingers and hopes ventilated pistons aren't in any future plans...)

 

[Lee_Burough]

Drive gently....A good idea....

When I listed a bunch of expensive parts above, I was not advocating you replace them as a method of troubleshooting....Rather, I would expect the Buick owners in your area would pitch in to help you troubleshoot....First by using one of their scan tools, and sometimes by replacing a suspect component with a known good component to methodically rule out each component as the culpret for your predetonation.

So, its more than a scan tool. Like Razor says, don't fail to contact the Buick owners on the Island, they are the best solution in your situation. They will enjoy the challenge of diagnosing your car

lee

 

[pvt num 11]

"we all need a little help, from our friends..."

 

[pvt num 11]

Thanks, Quicker6 (Derek) !

He stuck his scan-master onto my car, and we drove it around some. He thinks it could be my MAF, that or a fuel delivery/ignition problem. He doesn't think it's detonation, as I'm not getting any knock counts at all. We're going to swap MAF's (he brought his GN to work, like usual) and we'll see if the problem transfers itself to his car. If so, easy fix - just go get a new MAF. If not, I may look into ignition stuff, like the coil packs, wires and plugs. TPS voltages were a bit low, but he doesn't think it's enough to cause havoc with anything, and the voltages go up and down smoothly. A bit low on the closed position (.34 volts) and a bit low at WOT (4.6 volts).

We'll see what happens.

Oh, and I may be getting a cold-air intake, as I don't like sucking 120-degree air into the engine while stopped at a light...

 

[Razor]

Get the TPS up within spec. .38-.46

Always start with putting things where they belong, not replacing parts. Once the parameters are setup correctly, move to figuring what went wrong.

And... Leave the air intake alone. 120 is nothing.

careful not to add un-needed stuff that latter may cuase issues.

HTH

 

[pvt num 11]

.04 volts would be a big enough difference to matter? I'll play with it, see if I can figure it out.

 

[Razor]

.04 volts would be a big enough difference to matter? I'll play with it, see if I can figure it out.

Be amazed...

 

[pvt num 11]

0.42 with the car running now, and the idle is a tad better. It still stumbles under load. O2 readings are inconsistent (due to driving inconsistancies), but it reads around .460 when idling warm. I don't have a clue when that sensor was last changed, though.

 

[DaJoker]

Was your car showing any codes or was the check engine light on? My car has a similar problem with a hesitation when the turbo spools up on acceleration. It feels like its losing some guts but there has been no popping yet. I was figuring it was my MAF sensor and I have a friend with a scantool who will come by my house 8/4, but my check engine light doesn't come on. How does your car idle when you first start it, does it stumble and want to die. How about part-throttle driving , when holding a steady speed mine sometimes feels like it cuts out. Good Luck and let us know what happens.

 

[pvt num 11]

Upon start-up, it spools up to 2 grand, then falls back quickly to around 1100 or so, then it idles hot at 700 or so. Idles fine in and out of gear. Holds speed at part-throttle fine, it just doesn't like lots of boost sometimes. It tends to do it more if it's warm outside, less if it's cooler. Every once in awhile, it runs without a hitch. As soon as I dig out my multimeter, I'll go measure my coil packs. 11-13k is a normal reading, right?

 

[DaJoker]

You may want to check out 89tta.com, go to the Tech section and look for intercooler cleaning. The problem he has sounds kind of like yours. I am going to try mine this weekend so I will let you know if it makes that big of a difference. I can guarantee that mine has never been cleaned. Plus they have some good info on these cars to help with tuning.

 

[DaJoker]

Did you get your problem solved??? What was the problem, curious cause my car is in the same boat.

 

[83ttypecooled]

"pop"

Hi!
I have been through this whole mess. My Regal gave me fits with intake backfires and such. I could have sworn I was dealing with a secondary ignition problem, but you know what? It turned out to be fuel lean out. If I had strapped on a fuel gauge and taken a run, it would have been obvious. At that time, I wasn't running a scanner, either. That would have shown it with o2, block learn and integrator.As a matter of fact, the minute I hooked up my old OTC Monitor2000 and took a run, I knew I had fuel delivery problems.Anyway, a Walbro 340 and a great hotwire kit from my friends at Racetronix fixed it. In my experience, ignition is most often the culprit in misfire issues, but NOT always.
By the way, testing our ignition coils is tricky, at best, with a DVOM. I have seen several with less than 10KV output which ohmed out perfectly,right about 12Kwith no discrepencies between coils. Murphy's law, right? When you think you have it right, think again!
I wish you luck in your search for the problem!