Clogged convertor?

Subject: Re: Clogged convertor? Mon Oct 19, 2009 12:50 pm

Ryan, how long have you had an 04 Impala engine in your 95?

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Dave G
98 Riviera
Gutted, 3.8, 180, 104'S, front PEM, 3" DP & Cat, Caddy STB, GR2's. DHP 1.5

Subject: Re: Clogged convertor? Tue Nov 10, 2009 4:53 pm

AA wrote:

One way to test catalytic converter is to put car in neutral and rev the engine to the 3-4k range (when warm). According to GM:

"If the engine freely accelerates to higher RPM in Neutral, you can assume that the engine and the exhaust system are normal."

If there is any lag in getting into the upper RPMs, you might have a clogged cat.

If it were mine, I'd check transmission fluid level and color/smell immediately. Low or burnt fluid, or a failing trans, can cause the symptoms you're reporting.

Ok I tried this today.

The car in park will go up to about 3,500 RPM and sputter like... It will go upto 4K but it sputters throughout.

So that would signal clogged cat?

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1995 N/A, motor from an 04 Impala with replaced sensors!

Subject: Re: Clogged convertor? Tue Nov 10, 2009 5:52 pm

Not necessarily.
Have you checked vacuum readings as previously mentioned.?
Have you had a CASE Learn procedure done since swapping crankshaft position sensors.?

_________________
98 Riv, 102K Miles, EBC, LS1 Ft.Calipers, STB, Addco Rr Sway Bar, 180* stat., SSAC Headers, HF Cat, 1.9's,
105# springs, MPS 3.4, DHP tuned by the Deekster.

Subject: Re: Clogged convertor? Tue Nov 10, 2009 6:20 pm

Ryan from Ohio wrote:

AA wrote:

One way to test catalytic converter is to put car in neutral and rev the engine to the 3-4k range (when warm). According to GM:

"If the engine freely accelerates to higher RPM in Neutral, you can assume that the engine and the exhaust system are normal."

If there is any lag in getting into the upper RPMs, you might have a clogged cat.

If it were mine, I'd check transmission fluid level and color/smell immediately. Low or burnt fluid, or a failing trans, can cause the symptoms you're reporting.

Ok I tried this today.

The car in park will go up to about 3,500 RPM and sputter like... It will go upto 4K but it sputters throughout.

So that would signal clogged cat?

No, our cars have a rev limiter in Park/Neutral. It won't rev and that is normal. Drive the car.

Subject: Re: Clogged convertor? Tue Nov 10, 2009 7:39 pm

The purpose of the test is to see if it revs up quickly. If it does, your cat is not likely an issue. If it revs up slowly or with labor before it hits the limiter, you could have an issue.

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'98 Buick Riviera; Gen V 3.25 pulley, N*, VS Cam, 180 stat, Custom PCM (Powrtuner), headers & HF cat , 42.5 lb inj.

Grant-built/PRJ/Thrasher trans 3.29 gears, 7/8 chain, zzp hardened IS

Subject: Re: Clogged convertor? Tue Nov 10, 2009 7:53 pm

sounds like PCM mismatch. Need PCM from donor car and pinout of new PCM and old PCM - tehn use a pick to remove/replace pins in harness. there will be several but not all to move. IDK if the cams in the S III differ from those in the S I but if so then even matching all the sensors won't work, IIRC the fuel trim and timing will be off if you do that.

Albertj

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1998 with all fac. opts. (exc. CD changer and subwoofer); 209,000 miles. Mods: KYB front struts, extra noise barriers, fire extinguisher, Magnecor 8mm plug wires, 4-note horn, custom-made stainless exhaust.

Avatar is missing.

Subject: Re: Clogged convertor? Tue Nov 10, 2009 9:11 pm

Ryan, do you have a 3" DP or headers ? I still have the 321 stainless 3" test pipe and reducer (to 2.5") that came with the headers I got.

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Jason
1998 Buick Riviera: 4" FWI, 3.4" pulley, VS cam, "SLP" headers, 3" exhaust, ported s/c, Addco swaybars, STB
1987 Regal Turbo T

Subject: Re: Clogged convertor? Tue Nov 10, 2009 9:44 pm

Jason wrote:

Ryan, do you have a 3" DP or headers ? I still have the 321 stainless 3" test pipe and reducer (to 2.5") that came with the headers I got.

Its the stock stuff.

Just to be clear the 1995 Rivi had a Series 2 N/A motor in it. The S/C 95's were Series 1

The entire intake manifold, throttle body is from the 95' rivi.

The new motor, I had to swap out injectors, sensors, oil filter modular piece and the water pump modular setup and alternator stuff.

everything else is from the original 95 rivi. Just used the short block basically.

_________________
1995 N/A, motor from an 04 Impala with replaced sensors!

Subject: Re: Clogged convertor? Tue Nov 10, 2009 9:59 pm

got it.

_________________
Jason
1998 Buick Riviera: 4" FWI, 3.4" pulley, VS cam, "SLP" headers, 3" exhaust, ported s/c, Addco swaybars, STB
1987 Regal Turbo T