Mo_Jo_Jo

I've been kicking my *** the past couple days working on this car and getting everything together needed to put it back together.
I replaced the new pilot bearing after tranny shifting issues (after installing the new engine).
I finally got all the basics sorted out to get the car rolling on its own, with issues.
I can't get the car to idle. I think this is probably a TPS issue, but I can't find a sure fire way to check this without the test indicator... and then am I just adjusting the small throttle stop screw on the rear of the throttle body?
The car is dead at about 15% throttle.... nothing. It's like "blah" with decent power to ~4K.

Can anyone help me with ideas? I'm so tired of working on this that I can't seem to think of any ideas where to go with it.

87 TII
Atkins street ported S5 (~0 miles, S4 front cover)
RTek 2.1
RC Engineering 750cc pri. and sec.
no emissions and throttle body mod (per rotary ressurection)

Mo_Jo_Jo

Any help morning guys?

I'm going to inspect the fuel filter visually and check fuel pressure today.

I checked the resistance through the TPS. The TPSs' 3 pin plug gave me these readings:

a-b @ idle ~ 1.22K Ohms
@ WOT ~ 7.21K Ohms
a-c @ idle ~ 7.2K Ohms
@ WOT ~ 1.2K Ohms

I did also notice for the first few seconds of running, it's much more responsive to throttle.

arghx

iTrader: (3)

you need to check for vacuum/boost leaks first and make sure the timing is correct

On your RTEK, what throttle % does it say at idle? at WOT?

Mo_Jo_Jo

I just got off the phone with a guy at RTek and he says tps should be about 20% at idle, so I adjusted to about 20% and the car stays running, or responds to throttle for a little bit longer now ~10sec.

I also checked fuel pressure after the filter and was getting about 30PSI. This doesn't seem right to me, so I'm going to go check the manual now, but if you can get to me quicker all the better. With so many measurements given for pressure at differnt points, what measurement should I be looking for checking pressure in line after the filter with the engine running?

really anxious to get this thing running.

Mo_Jo_Jo

I adjusted the TPS to read 20% throttle through the RTek, and that seemed to help some along with the next part...

After rerouting some vacuum lines, I was able to get the car to respond to throttle much better... but still won't idle. I drove the car to the store and shut it off. When I left the store, the car started behaving the same as before changing lines around. The car is dead from 10-50% throttle. 50% plus makes nice power, keeping the revs down on the new engine. Now the car is screwy again...

Any ideas where to go with this car?

Mo_Jo_Jo

After setting the TPS to 20% at idle, wot reads ~91%

Is this accurate? What's the best method for checking vaccuum leaks? I can't really check timing because the car won't idle.

TIA

I'm begining to question the primary injectors sealing. After installing them, it seems like the injector body is hitting the water jacket

Mo_Jo_Jo

When the hesitation comes on, the AFRs are reading way lean. There's definately some marking to the injector's body of the rc injectors.

Mo_Jo_Jo

After finally determining the cause of the idling issues, the RC engineering injectors are too large to be installed properly in the primary location. This keeping the injectors from sealing completely and creating a leak. I've reinstalled the 550cc factory injectors in the primary location and left the 750s as secondaries.

I'm having some issues now with surging at ~3000 RPM.

AFRs look good under load (~11.5), with cruising from 14-16 (~10% throttle).

Any ideas what the surging may be about?

Mo_Jo_Jo

Removing the RC primary injectors, and adjusting the idle/setting the TPS pretty much solved my idle issues. The idle is set to ~750RPM and 20% TPS (via RTek). The surging is still present, but the clutch is slipping pretty bad. After verifying my timing is set spot-on, I plan to purchase a new clutch and resurface the flywheel, then check the surging again... unless it could be a symptom... still. Now I have another problem.

at idle, the car runs constant ~13:1 AFR. After idling for about ten seconds and taking off (traffic light scenario), the car will break up at about 40% throttle and drastically lose power, like can't even take off. The AFRs at this point go way lean (~18-19:1). If I give more throttle the car will clear up and I see AFRs drop to about 11.5:1 under load. What should I look for here?

After continous driving, the problem does not arrise. Only after stopping, at a stoplight does this happen. Then, once it clears up the problem only comes back after stopping agin.

HELP PLEASE!

calpatriot

I would get an analog (needle indicator) ohmmeter and check the TSP resistance through full sweep to see if there are any dropouts. Also, the 7.2k ohm reading seems abnormally high; check the FSM numbers, but I think it should be in the range of 4.5 -5.5k ohms.

If you disconnect the TPS, a stock ECU will default to WOT numbers; if the car runs well there, it might point you to something (bad TPS?). I do not know if the aftermarket ECU you are using will do the same, tho.

Mo_Jo_Jo

I am able to see the TPS sweep smooth and clean through the RTek's log function, showing no drop outs what so ever. The past few days here have been without rain, so I believe this could have something to do with it.... I will verify this once it rains again

The car runs very well now that it has not been raining.

In the meantime, is there a common occurance that this may sound like?

misterstyx69

iTrader: (142)

I have a Crazy Idea
check your Cas for Corrosion.
if it Rains and you get mositure in the Cas it will go all Bonky..
I've seen Guys running the Cas without that plastic plug on the Cover of the Cas.
I myself wouldn't like that.

Mo_Jo_Jo

I had the same problem yesterday afternoon, leaving work. The car hesitates really bad, like it's not getting any fuel. Confirming the reading of my wideband, I can see, clearly (~19:1), it's not getting any fuel during these 'episodes'... and it was not raining yesterday.

What are you referring to, about the CAS, when you say corrosion... what part is susceptible to corrosion?

Thanks!