chasing my tail
Thread Starter
Cruising
Joined: Apr 2013
Posts: 14
Likes: 0
chasing my tail
first off I have a 89 s15 I put a 86 corvette 5.7 tpi into that's why im here... the motor is running really rich and I cant seem to figure out why.... I have replaced everything: new 22lbs injectors, maf, esc, ecm, tps, fuel pump filter and regulator fuel pressure is around 38... im on my third set of plugs cuz its fouling them out so fast.... please any input would help
Le Mans Master
Joined: Oct 2008
Posts: 9,758
Likes: 49
From: Houston Texas
first off I have a 89 s15 I put a 86 corvette 5.7 tpi into that's why im here... the motor is running really rich and I cant seem to figure out why.... I have replaced everything: new 22lbs injectors, maf, esc, ecm, tps, fuel pump filter and regulator fuel pressure is around 38... im on my third set of plugs cuz its fouling them out so fast.... please any input would help
Melting Slicks
Joined: Aug 1999
Posts: 2,240
Likes: 42
From: Baltimore, MD USA
If the engine has never run correctly it could be anything from
the tune to wiring errors.
If after the swap it ran good but now is rich the best way to
trouble shoot would be to use a scan tool or scanning software
that runs on a computer and attaches to the diagnostic connector
which will allow you to look at the engine sensor values. Parameters
llike TPS sensor, MAF, ECT, O2 sensor , Open or Closed loop, injector
pulse width, Blms, Integrator etc... can all be displayed.
If you short A to B on the diagnostic connector and have a Service
Engine Soon inidicator hooked up it will also tell you if any engine codes
are set.
Did you replace the Engine Coolant Temperature sensor screwed into the front
of the intake manifiold?
That tells the computer the engine temperature.
the tune to wiring errors.
If after the swap it ran good but now is rich the best way to
trouble shoot would be to use a scan tool or scanning software
that runs on a computer and attaches to the diagnostic connector
which will allow you to look at the engine sensor values. Parameters
llike TPS sensor, MAF, ECT, O2 sensor , Open or Closed loop, injector
pulse width, Blms, Integrator etc... can all be displayed.
If you short A to B on the diagnostic connector and have a Service
Engine Soon inidicator hooked up it will also tell you if any engine codes
are set.
Did you replace the Engine Coolant Temperature sensor screwed into the front
of the intake manifiold?
That tells the computer the engine temperature.
Melting Slicks
Joined: Aug 1999
Posts: 2,240
Likes: 42
From: Baltimore, MD USA
Here's the block diagram showing how the MAF power
relay and the burn off relay are connected.
If you can't read the diagram, right click on the diagram,
save it and then print it out.
relay and the burn off relay are connected.
If you can't read the diagram, right click on the diagram,
save it and then print it out.
Last edited by Hooked on Vettes; Jun 26, 2013 at 05:25 PM.
Thread Starter
Cruising
Joined: Apr 2013
Posts: 14
Likes: 0
I ordered 22lbs ford injector I hope that's what they sent... they all ohm at 15ohm's... when I unplug the maf there is no change in how the motor runs.... both relays are new and harness is also new from painless wiring...
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Drifting
Joined: May 2013
Posts: 1,736
Likes: 31
From: Reno Nevada
Follow the flowchart to diagnose code 34, and see if you can get number from the injector. Ford 22 scares me.
Thread Starter
Cruising
Joined: Apr 2013
Posts: 14
Likes: 0
o2 sensor is new and I removed the cold start already thinking that was the problem... another strange thing is it ran like crap with the vette computer. so I put the s15 computer in it and it ran great but was still rich then it backfired once on the freeway and it went back to the same old thing
Melting Slicks
Joined: Aug 1999
Posts: 2,240
Likes: 42
From: Baltimore, MD USA
Drifting
Joined: May 2013
Posts: 1,736
Likes: 31
From: Reno Nevada
Okay, the mass air flow relay, and burn off relay are different. Did you get them correlated correctly? Also, do not use the S10 speed density memcal (calibration module) as it may cause damage to devices not being designed for your system.
My last statement still stands.
My last statement still stands.
Thread Starter
Cruising
Joined: Apr 2013
Posts: 14
Likes: 0
I am aware the relays are different I did get the right ones... according to the chart above I need a new maf sensor but I just put this one on??? oh and yeah the s15 computer worked with the vette motor.... if I unplug the maf while its running shouldn't it alter the engines performance cuz it does nothing
Drifting
Joined: May 2013
Posts: 1,736
Likes: 31
From: Reno Nevada
If you follow the flow chart it will determine for sure if it the MAF sensor. The fact that nothing changes would lead one too think it's bad. The vehicle may have operates with the S10 memcal, but it surely was not properly. Guessing, or Harry Potters magic wand won't fix it. You must follow through with the proper components and work the bugs out. I've always said the real work starts once you turn the key.
Thread Starter
Cruising
Joined: Apr 2013
Posts: 14
Likes: 0
ok so I put the vette computer back in and getting a code 33 its has to be a bad maf im getting power to it but it doesn't seem to be doing anything..... now before I go putting another maf on it is there anything I could have done to burn this one up?
Drifting
Joined: May 2013
Posts: 1,736
Likes: 31
From: Reno Nevada
Running the S10 speed density memcal is not good. I would have to sit down and study the wiring diagrams to make an educated guess.
Here's a flowchart to code 33:
http://www.chevythunder.com/maf_code_33.htm
Follow it, as the other memcal could have ruined one of the new relay's too.
Here's a flowchart to code 33:
http://www.chevythunder.com/maf_code_33.htm
Follow it, as the other memcal could have ruined one of the new relay's too.