What's the best way to clean intake valves?

[Nayov]

Short of removing them from the cylinder head and power wire brushing them that is. Do any of those mechanic-in-a-bottle concoctions / snake oils work? I'll try anything at this point. What about MMM and Seafoam? If I use a top tier gas brand (yes, I had been only buying convenience store cheap stuff) how many tanks before I see results, if any? Lastly, what about a so-called fuel injection services -- do they address intake valve deposits?

I'm trying to cure chronic pinging that has not been alleviated by the use of premium, using cold plugs, the tweaking of ignition timing, EGR, etc. It also surges when the engine is cool; both problems directly related to deposits on intake valves according to the e-experts. Sentra with 235,000 miles.

 

[spasm3]

how long has it been pinging?

 

[Steve S]

Try Gumout with Regane . I would use it double strength and do it several times . The money it would cost to R/R the head and clean the valves and do it properly may or may not be financially be resposible. So it would be worth trying the chemical approach.

 

[Steve S]

You may be able to remove the intake manifold and walnut media blast off the carbon deposits.

 

[HTSS_TR]

Gumout Regane is on sale at Autozone for $4.99 after $2 discount.

 

[spasm3]

Does this engine have a knock sensor? Something to look at.
I agree with SteveS on the regane, use it with a mid grade of a top tier fuel.

 

[Nayov]

Originally Posted By: spasm3
how long has it been pinging?

18 years (for real)

 

[Steve S]

Originally Posted By: spasm3
Does this engine have a knock sensor? Something to look at.
I agree with SteveS on the regane, use it with a mid grade of a top tier fuel.
Yes on checking the knock sensor ...i thought about it

Lean condition when cold? Coolant temp sensor or air temp sensor ?

 

[Lethal1ty17]

run a few seafoam cycles, use a gas like shell v-power with alot of cleaning agents, run some seafoam or MMO through the gas tank, and repeat. should clean it right up, and lastly, dont be afraid to redline it, it actually helps clean out some of the deposits that you wont get while just putting around town.

 

[shanneba]

Run a bottle of Red Line S1 through it.

 

[StevieC]

Amsoil PI fuel additive or Red Line S1 and top-tier fuel, might have to do a couple tanks of it.

Add to the fuel and run the tank almost to empty, and then refill with more additive and top-tier fuel.

I would recommend Shell V-Power during this time as it seems to have an insane amount of cleaner in it.

You might also plug the vacuum source to the EGR valve at this time so it runs hotter and leaner.

What temperature thermostat do you have in this engine? I would recommend a 192 if possible to ensure it's reaching operating temperature.

Also what is the timing set to? It could be too far advanced and this can lead to pinging as well.

Also check to make sure that your spark-advance is free and working properly inside the distributor.

Are you sure the valves are gummed up or just thinking this because the EGR is working?

 

[spasm3]

Originally Posted By: Steve S
Originally Posted By: spasm3
Does this engine have a knock sensor? Something to look at.
I agree with SteveS on the regane, use it with a mid grade of a top tier fuel.
Yes on checking the knock sensor ...i thought about it

Lean condition when cold? Coolant temp sensor or air temp sensor ?


Its pinging cold? if so then you have a timing problem! I'm not familiar with import cars, but does the ecm control timing or can you set it with a timing light?

 

[The Critic]

Check MAF and the fuel trims.

 

[StevieC]

He said he has had this problem 18 years so the vehicle is old and doesn't have all this non-sense guys...

 

[spasm3]

Originally Posted By: StevieC
He said he has had this problem 18 years so the vehicle is old and doesn't have all this non-sense guys...



like i said i'm not familiar with imports. But my 93 olds has maf and other ecm sensors and its 17 years old.

 

[StevieC]

I stand corrected, I goofed I did my math wrong on the 18 years and was thinking the car was from the 80's.

My mistake, it could very well have a MAF on it especially if it's "import" because they were some of the first to do this instead of MAP sensors.

The timing would most likely be distributor though... Most "imports" didn't do away with this until the mid to late 90's.

 

[Falcon_LS]

Lubro-Moly Valve Cleaner. Get 4-5 cans and that should sort it out.

 

[mechtech2]

Use an in tank cleaner.
This works slowly, but can hep a lot, and not just with valves.
Gumout REGANE or a strong Chevron Techron product are very good. Redline SI-1 is good and Amsoil has a superb product.

 

[Nayov]

I filled up with Shell premium and a bottle of Techron Concentrate, we'll see. Also bought 3 more bottles for the next 3 tanks. If this actually works it'll be nothing short of an automotive 'miracle.' I wanted to use Chevron gas but this state is so backwards that there are NONE in the entire state!

 

[Nayov]

Update: After 3 bottles of Techron and 30 gallons of Shell V Power that Gosh-awful noise is completely gone even on the hottest day, engine lugging, A / C running full tilt and it's back on regular fuel (Top Tier of course from now on).