I picked up a 1st gen S/C and it was in pieces from the guy I purchased it from. For anyone out there with a 1st gen my question is where do I put gasket material when putting it back together? Pictures would be good here but I am mainly wanting to know between the intake top part and rotor pack body housing. Is it metal to metal when installed together or should I put a bead of gasket material between the surfaces? It looks very clean on mine so I would assume I would not put anything in there but I thought I would ask. Also, does anyone have a leftover throttle bracket they could sell me? I believe this is the last remaining part I need before I install. Excited to S/C my swap finally!!

 

I just put a bead of RTV along those surfaces and didn't have a problem.

 

You might take some pictures to show us, and then call Magnuson in California.

 

Thanks Ace, did you use just the black stuff? I will take some pics tonight and post them. I have some time before I install. I am still chasing a hesitation problem. It is driving me crazy! The engine coughs when you pound on the throttle and waits a second, kinda backfires, then takes off and is fine. So it really only happens at WOT.. I have not had much time to do some troubleshooting but when I ran some live data the TPS was showing only 65 to 75% at WOT. I changed it and it runs great except for this hesitation issue. I also scrubbed down the throttle body, MAF with MAF cleaner, Removed and cleaned injectors up, and new air filter, checked the coils and are within spec. All items still don't help the issue (oh yeah, no CEL for this issue). I am thinking it could be a faulty plug even though they were new last year. Next step is to remove all plugs and check them out. I will do compression on the engine while the plugs are out. I also am going to change the fuel filter since its been a year and the beast sat for quite a few months prior to the changeover. Any thoughts on this so I can concentrate on what to look at??

 

Does the hesitation issue only happen at ~1800rpm or a particular RPM range? I had an issue like that, never did figure it out, it just went away.

Yeah, I just used the black RTV. It was bare metal when I took it apart and I just wanted something on it when I put it back together.

 

Hmmm. I will have to check the rpm ranges. So far I have only noticed it when I tromp down on the pedal. Kinda strange. I just hope its not a major issue. Before it hesitates it sounds almost like a whoosh sound which makes me think it is a vacuum leak somewhere. I tried the carb spray technique and havent found anything. Another issue that might be tied is my brakes sometimes feel spongy. I replaced my front disks, calipers, and pads and still experiencing the spongy feel. It mainly happens when the air is on. I am wondering if I have hooked up my vsv's wrong when I did the swap. Lots of stuff to check Any thoughts?

 

A vacuum leak was my first thought, I would check that over real careful, also check the intake after the MAF sensor. Naturally make sure all the vacuum lines are hooked up correctly to start with and the lines themselves are all good.

After that it would seem to be an electrical/sensor issue.

 

So this weekend I did some investigating on the hesitation. I found a vacuum hose with a small hole in it replaced it and was excited to try it out and of course it didn't fix it. So I changed the fuel filter since I had a new one and it had been a year and it helped some but the lag is still there. I did test it at different rpm's and found that it really only happens when it is idling and then crank the throttle down and it kinda hesitates then burps a little and takes off. I pulled all the plugs and they look fine and checked all the wires as well. They are all a year old and toyota OEM. Could the exhaust cause this type of issue? I guess maybe test each of the sensors starting with MAF? I did record some live data but I am still new at OBD diagnotics so I don't really know what to look for. My O2 sensors seem to "may" have a problem but not sure.

Would anyone be willing to look at my data if I emailed it in excel? I made a few graphs of some of the important ones. Or does anyone know of a good website that teaches you to know what to look for? I searched and searched but nothing seemed to break it down well.

 

Biggest thing to look for in your case are any sudden changes or anything that looks out of place when the hesitation happens vs the rest of the time.

If you made a graph you could post it here in picture format, or a screenshot of the data you have and we can take a look at it.

 

In order to get the pictures to you guys I had to put them on photobucket. here is the link. Let me know if it does'nt get to you (you may have to post in your browser). Sorry for the PIA, my browser would not let me attach anything for some reason.

http://s1267.photobucket.com/albums/jj550/timmjk/

Jason

 

Pictures are tiny, can't really see what is going on but from what I can make out nothing stands out as being an issue. The O2 signal should look like that so I would not worry about it unless you get a CEL for it.

 

Ok cool. Did you try to double click them? I was able to expand them by double clicking them but it might be cause I own them. The only thing I was thinking with the rear o2 is that sensors waveform looked quit goofy (not a nice sine wave) to me and during idle it is not hovering around mid point but way low.. But again I dont really know what I am looking at.. Thank you for taking time to help..

 

Says the user doesn't exist now, I think you linked to the mobile site which is why they were so small.

 

weird.... try this.

http://s1264.photobucket.com/albums/jj491/95runner/

My last account would not even let me get back in at all. Strange. Sorry man..

 

Really hard to tell anything from those. These are best looked at live when you are making it happen. See what changes.

I don't see anything that jumps out as being an issue.

 

Thanks for taking a look.. I will try it later tonight.. Thanks again. In your opinion is the other things I should be looking into? With this being a swap maybe look at my wiring again just to be sure I havent messed something up???

I will watch it tonight and see if something jumps out at me. I will save it as well and post it up as well. Thanks again for giving me some time..


Jason

 

Well, it would seem to be either something to do with the TPS sensor or a vacuum leak as that is generally what will cause issue during a sudden WOT situation but it could be anything.

 

Hey Ace - So I did the runs finally last night and right now nothing is really jumping out at me.. I did notice the my long term fuel trim % on bank 1 is pretty much constant at -14.85%. It will go up slightly to around -9% only when I romp on the throttle. I changed the TPS a couple weeks ago because the data didnt look to good on it. It is now basically staying right at 9% when idling.

The only other thing I noticed is the short term fuel trim on sensor #2 is constantly -1 and never varies. Also, the rear 02 sensor voltage is hovering around 0.05 and then spike all the way up to 0.8 when I rev it for the hesitation to occur..

What do you think I should be looking for in your opinion at this point? What would be good to plot out and review??

One thought I have - I had remove one bolt on the crossover post on the driver because it was cross threaded and could go down all the way onto the pipe.. Could this really be causing a hesitation issue if the other two are down tight?

 

An exhaust leak could account for it if it was bad enough but you would hear it if that was the case.

Do you have any CEL's? If the short term trim never changes that would lead me to think an O2 sensor issue. It is too bad you don't have a wideband. If you could see the AFR's that might shed a lot of light on what is going on.

Issues like this are generally fueling related anyways.

 

No CEL at all. It is the rear o2 short term trim that never changes.. It is always negative 1 and the long term is pretty much neg 14.85.. Kinda strange.. What is wideband? Is this what is on the newer runners? Like 2000? Sorry kinda new at diagnosing with the whole fuel system stuff..

Do you suggest replacing with a new one at this stage and seeing if I have changes? I forgot to mention I also have kinda crap milage.. I get around 13 mpg with a manual and stock tires. It's a lot of stop and go but I would think I should at least get above 15. I thought when i regeared from 4.88 to 4.3 it would get better but has not... Oh well.