Cornholio7979

iTrader: (1)

I just finished putting together my 89 L98 IROC/Z28 that's been apart for over a year and a half. The engine was rebuilt at a machine shop, and I've dropped it in the car and plugged everything back in.

The engine/components are all stock or stock replacement. I've added a 140 amp alternator with the big 3 upgrade from Innovative Wiring, and a new ground strap from engine block to chassis. All vacuum lines have been routed correctly, everything cleaned if not replaced.

The car will start, but only with my foot on the gas. The engine runs real rough and heats up quickly. I mean in less than 5 minutes, the engine coolant goes from room temp to 220 degrees while still on jack stands. I've tried taking precautionary steps to prevent the fuel from becoming garbage by adding heet months ago, and adding fresh fuel to the tank before starting it. There might be bad gas left in the tank. All the residual gunk was burned out of the exhaust during a 1 minute period only for the first startup the engine has had in years.

I do not have a fuel pressure gauge, but I'm thinking that might be a good place to check next. What would cause my engine to run this crappy? I've been working on this car for waaaaaaay too long, please help me figure this out.

-Cornholio

Krik

iTrader: (4)

It is hot as hell this summer. Make sure your fans and water pump are working.

Cornholio7979

iTrader: (1)

I know the temp is a direct result of the engine running poorly. I checked all the vacuum lines, replaced most of them too. I got video of it running poorly, and will upload it tomorrow. I'll list all the specifics with the video tomorrow. Need help!!

TTOP350

iTrader: (8)

You may have a airpocket in the cooling system. Also make sure the timing is set correcty..

Cornholio7979

iTrader: (1)

Timing was set with the ALDL pins jumped and the EST unplugged to 6 degrees BTDC. The air pocket will get fixed when the car can idle.

Car Running Fail Video

Watch this and get inspired. Tell me what sounds wrong with my L98.

PS: I haven't uploaded video in years, so if there's a better way to post, I'd like to hear it.

-Cornholio

Cornholio7979

iTrader: (1)

Watch that video and you'll hear how bad it's off. I think its a sensor or signal giving me trouble.

I once had datalogging abilities, but my gear disappeared when I shared a garage with crackheads. I ordered the apu1 from Moates and it should be here before the end of the week. Maybe I'll see a painfully obvious data set pointing the finger at the appropriate sensor.

Until then, does anyone hear a familiar crappy running engine?

New Parts:

All 3 temp sensors
EGR valve, oil pressure sender/switch
thermostat
water pump and under-drive pulley
alternator and UD pulley
crankshaft UD pulley
radiator
radiator hoses
vacuum lines
"Big 3" @ InnovativeWiring
chassis to block ground strap
coil connectors
fuel filter
Optima yellow top
SLP runners

Cleaned(with the appropriate cleaning agent and electronic safe) Parts/Connectors:
The machine shop that rebuilt the engine installed the old knock sensor. I cleaned thoroughly and installed the rest.

Fuel injectors(sensor safe agent and nylon brush) and o-rings
MAF sensor
oil cooler lines
air temp sensor
pcv valve and hoses
wires(triple checked and labeled on both ends)
cap and rotor
coil

I set base timing 6 degrees BTDC with ALDL A and B grounded and EST bypass disconnected. I set the proper TPS voltage. Gauges work, except for the tachometer which is showing about 600rpm without the key being on. With the ignition in the ON position, it zeros out.

Any ideas?

Cornholio7979

iTrader: (1)

Replaced the MAF sensor today, no major developments, but the engine does seem a bit smoother. I feel like it's a step in the right direction, but the engine should be able to start without the gas peddle and be able to idle. I'm going to replace the IAC next. Some help would be appreciated.

Cornholio7979

iTrader: (1)

Replaced the IAC valve today. No change. The car was disassembled only for a head gasket, and otherwise ran perfectly. I've replaced almost every sensor on the engine. I'm running out of ideas, so I'm probably going to start from the beginning again soon.

Cornholio7979

iTrader: (1)

I've been dumping all the old fuel in case in went bad. I put some fuel stabilizer in more than once over the 18 month down period.

I forgot about YouTube... So a bit easier to view now, the video of my car running awfully.

85IROCzzz

iTrader: (1)

Is the firing order correct?

dabomb6608

iTrader: (3)

Might be worth it to check the fuel pressure. My dads Corvette(TPI) had similar problems. Replaced the pump and all was good. But it is WAY easier to change on the vette.

Cornholio7979

iTrader: (1)

Dumped all the fuel, and filled up with 5 gallons of new gas and 5oz of B12 cleaner. If the fuel pump were bad it would pump at full capacity or not at all, right? Any suggestions on a cheap fuel pressure gauge? Does a parts store offer one as a loan-a-tool.

I double checked each wire and all are correct.

I also tightened down all the exhaust manifold bolts and a few were loose, so there's less noise in the engine bay.

I was able to get the engine to idle tonight, and it's smoothing out. I think the fuel wasn't helping, but now maybe my injectors are cruddy. I've ohmed them all out to within 1 ohm of each other around 16-17 ohms, 3 separate occasions, so on that side they're still good.

I did get a code 44 tonight once the engine warmed up. I got an ALDU1 from Moates but haven't figured out how to set it up yet. Still waiting for an e-mail from Moates to get the big picture from my ecm.

Any ideas on the code 44?

I also had some liquid pop out of an AIR tube connection at the driver's side exhaust manifold. I'm tightening them down again as well, but what would cause liquid to come out of the exhaust without it being coolant? I'm in Las Vegas, so there isn't any moisture other than my evaporative cooler blowing into the garage.

Help!

Cornholio7979

iTrader: (1)

I've gotten the car to idle a bit, but it surges from 500rpm to 1000rpm. Also, when I hold the pedal to 2000rpm, the engine will surge +/- 250 rpm. Any ideas?

dabomb6608

iTrader: (3)

Sounds like with the cleaner in it that it is getting better slowly. It isn't doing the no idle thing anymore so I would rule out the pump. As I said, that was just from experience with what my dads car did.
What did the liquid smell like?

Cornholio7979

iTrader: (1)

Not good. It smelled partially like it went bad. It was "fueled down" with some good new gas a few weeks ago. When draining it, I saw it pool up in a funnel and was brownish in the middle and clear on the perimeter.

ruiterman

Are all the cylinders firing or "running"? When we first started my sons car after the rebuild it sounded very similar. I was able to determine that 3 cylinders were not running well by feeling that the exhaust header for those cylinders were not getting very hot.

We found two issues
One, the exhaust side rocker arms for those three cylinders were not adjusted properly and the valves was not closing all the way making those cylinders run so lean they wouldn't fire.
Two, although the timing said it was correct, we were way way retarded on the timing causing it to heat up really fast and run hot. This turned out to be the harmonic balancer had slipped and so we were not setting the timing where we thought we were.

Just a couple of ideas.

dacuma

I agree, yeah I doesn't sound like your firing on all cylinders. I didn't see if you did plugs, and another thing you mention your tach looks like it's off. When you did the cap rotor how did your dizzy look, was it rusty inside? If so that could be a prob also.

dacuma

I would also got to the tech board and ask vader and those guys over there, They've always got really good advice also. Good luck!

Cornholio7979

iTrader: (1)

After admitting defeat and a lack of time due to school, I handed the car over to a mechanic. Took him a while and a lot of head scratching too. Problem was the gaskets on one the upper plenums were reversed. I don't know how I could miss that, but he missed it while disassembling and reassembling the upper intake assembly a couple times until he blew smoke in the intake to watch where it was leaking.

So now it runs.

New problem. No reverse, and shifting forward is bad. It shifts too late(needs higher throttle), so I'm looking at the TV cable tonight to make sure it's connected in the transmission and calibrated at the intake. Any ideas why it wouldn't have reverse now?

dabomb6608

iTrader: (3)

If the tv cable was out of adjustment then you might have done damage to the tranny and lost reverse do to the damage. The 700r4 is really picky when it comes to tv cable adjustment.

Cornholio7979

iTrader: (1)

I've been through way too much with TV cables on my firebird, so I'm quite familiar with them. I was hoping the cable might be responsible for the forward shifting being off a bit. I don't think it has anything to do with reverse, but the transmission was at 100% before the engine went down.

Yesterday was the first time the car drove in 2 years. If I can't find that the TV cable is responsible(fingers crossed), then the problem is most likely internal. When I get home from school today I'll take some time to diagnose the transmission.

IIRC, the 700R4 has just the TV cable externally that could cause something like this. Unless a transmission cooler line was crushed or bent without me seeing it (I was under the car watching lines when the engine was lowered in) I don't think the problem will be on the outside of the tranny. Didn't know if something might be linked to something else I did that you guys might see on this thread. If I can't figure out where reverse went, it's going to a shop. I don't have the time or tools to disassemble my transmission right now. School takes up all my time!