new here 3100 questions

[pontiac3100]

whats up. (long post sorry)
i'm new here and i've searched on the two topics.

the car:
1994 pontiac grand am gt 3100v6 sfi

my 1st one is: it's time to do the lim gasket.
so i figure i could probably swap the uim/lim and t/b only of a 99+ 3100uim/lim or 3400uim/lim.

i know i'll probably run into the egr issue...but anything else??


also i'm having...i assume and ignition problem.
this has been going on for a week.

when the rpms rev 3k and up it either pops or bogs.
followed by the smell of an engine running rich.(when i have the windows cracked)
this happens sometimes.

also the tach twiches at the higher rpms...

and i think the pcm does'nt know whats gong on becuase i hooked a scan tool up to it.
when your on the screen where it shows what position the iac in,tps, coolant temp, trans temp, etc...

but when you egt to a section it shows:
quad driver 1: bad
quad driver 2: ok
quad driver 3: ok
quad driver 4: bad

i think that has something to do with it....

sorry for the long post. so any advice??
thanks
and i like the site!

[Azrael]

For the large-port intake swap you'll also need to tap the coolant line in the lower manifold with a 1/2" NPT hole tap. Plus you'll need a new coolant sensor (AC Delco# 213-815) with the connector (same as TPS connector) to make the coolant gauge work. You can see more detailed info at www.3400swap.com

As for the quad driver issue I'll let someone else chime in. I don't see anything about it on the PCM wiring schematic I have for our cars.

[pontiac3100]

actully i was told the older 3400 (minivans)will swap right in...except for the egr valve?

[Azrael]

It's very close to a drop in but not a direct one. The same things mentioned earlier apply to all 3400's to my knowledge.

Looking back I realise you're only swapping the intakes and not the heads so the coolant sensor I mentioned doesnt apply. So forget I mentioned that. I get ahead of myself sometimes.

As for the EGR you can get an adapter plate from this site's store to fit the old EGR valve to the newer intake manifold. You'll still need to get the necessary gaskets along with the EGR pipe from the intake to the exhaust manifold from any 96-99 3x00.

[bszopi]

You will also have to clearance the bottom side of the LIM to clear the stamped rockers that are found in the 94 engines.

[pontiac3100]

well i might as well just get any 3400 lim/uim.

how will i clearance the lim for the rockers....and why does the 94 3100 have different rockers compared to 95+?


p.s. do anyone know about the quadriver

[bszopi]

http://60degreev6.com/gallery/browseimages.php?do=browseimages&c=7&page=2

Check out those pictures comparing small port 3100s and large port 3x00s. You will see where my rockers clearances themselves as well as where the large port manifold is clearanced from the factory.

They started using roller rockers on the heads sometime in 95 (some 95 3100s will still have the stamped rockers). Why they did it? Who knows... But all the 94 heads I have seen do not have the notch in them that is required to install the roller rcoker pedestals, so I can't recommend upgrading to the rollers either.

[tractorman]

You're opening up a BIG can of worms here. As the cranky old fart on the site... my humble opinion is that you ought to fix it right, and don't go screwin' around with a perfectly good engine. We get posts here all the time where somebody tears their engine apart on a quest for 10 more horsepower and ends up with a boat anchor. I have no idea what your skills/experience may be, or what you want out of the car- but be sure you know what you're getting into there.

That said... I don't THINK you can put a 3400 LIM on a '94 3100 without swapping the heads. Somebody correct me if I'm wrong... but not only will the ports not match up due to size differences, but I don't think they'll even align quite right. Even if they did line up (which I doubt)... I don't think you'll gain much having those big 3400 intake ports when they get necked down to those little 3100 ports in the heads. I think your only upgrade option is to swap the intakes AND heads off the 3400.

I'll concur with previous posters in that you'll need to address the heater hose pipe connection into the LIM just under the thermostat. It's probably about the right size to tap out to 1/2" pipe (which is not "1/2 inch" OD, btw) ... but that fitting sucks anyway. I'd eliminate it if possible. I'd try swapping over the whole heater hose pipe, assuming that it's routed more-or-less the same. It's a much simpler and better design on the 3400. The EGR will require an adapter. I don't know about clearancing for ball'nsocket rockers... sounds like askin' for trouble- but that's a moot point if the '94 heads won't work.

I say leave it stock and fix it right... and quit screwin' around. Just my $.02.

[tractorman]

Hmmm... I seem to have forgot. You should probably look into your current problem before you tear it apart. Sounds like a massive vacuum leak to me.

Why do you think it's time for the LIM job?

[pontiac3100]

you think the reason my car is acting like this is because of a vacuum leak??
i dunno.

they said the 3x00 9is common for the lim leaking...
maybe i could wipe the side of the engine and keep an eye on it.

but whats pissing me off is this high rpm/take off problem.

every once and a while when i take off around 9-15mph the engine'll bog.

so i pulled into an alley and did a lil' "brake torque".
and around 10mph the engine will bog....i dunno if thia has anything to do with the quad driver.

as for the intake...if i decide to do it, would it be better than just to have them port the uim/lim??

[tractorman]

I misread your opening post- this part:

when the rpms rev 3k and up it either pops or bogs.
followed by the smell of an engine running rich.(when i have the windows cracked)
this happens sometimes.

I didn't notice the "when", and assumed that the engine was revving to 3000 on its own.

But seeing as it starts acting up when YOU rev the engine (I'm feeling more literate today)... no, I don't think you have a vacuum leak. I think you may be on the right track with the ignition.

I don't know that a "quad driver" is on this engine- haven't run across that term. For that matter, I don't recall ever reading about an "egt" on this engine. Maybe somebody else around here is familiar with it. Is the car throwing any codes?

Does it miss when revving it up in neutral, or is it mainly under load, while accelerating?

An ignition problem on the high voltage side (coils, plugs, wires) will generally show up under load. If your plugs and/or wire are old, I'd start there first. Also, these 3100's are bad about corroding the connections on top of the coil packs.

About the LIM gasket. If it's leaking, you'll generally see one of two things. Either it'll get coolant in the oil- which you should definitely check for regularly. Or it'll leak exteranlly- along the gasket on any of the 4 corners of the engine, just above the bottom of the V. It WOULD be a good idea to wipe it off and keep an eye on it. But if you're not seeing either of those problems, then you probably shouldn't mess with it. If it ain't broke, don't fix it.

As for porting the intake- you have very little to gain by doing that. Even the upgrade to 3400 heads and intakes is only worth 15hp... and that's with proper tuning. That's a lot of time, money, and risk for a mere 15hp. I say get it running right, and leave it alone.

[bszopi]

Do a search for "quad driver" from the search button above. There were a few threads discussing quad drivers a few years back that might provide a little more help or insight for you.

[pontiac3100]

well there's not really any info on the quad driver.

when i rev her in nuetral you can hear it...it's there but not to the "untrained ear".

and what pisses me off is today i was on the highway...and the tach needle was just twitching and the engine was stumbling.

and this did'nt even trigger the ses light...i'm at a lost

[pontiac3100]

today this morning it was fine.
but when i went home for lunch i started her up...
it was missing....
there's this link on how to test the icm and coils with a dvom.
i'll update later.

[pontiac3100]

okay here's a little update.
i was reading up on it...and i read that the tps sensor causes this to happen too.

so i disconnect the tps and started her up...she idle like at 500rpm the ses light popped on.

but she idled?
she didnt rev to 2-4k rpms?

so what did i do.
put her in drive and push the gas....and she responded?!

i could'nt belive this..i was able to drive her with the tps disconnected?!!!

but it did'nt solve my problem.

something's not right...