Will the jobs report be the spoiler?

April's jobs report is expected to show a spring back in hiring—and in the economy.

It is also the one piece of data traders say could move the clock up on a Fed rate hike, if it is strong enough. But the mood around it turned sour Wednesday, after ADP reported just 169,000 private sector payrolls for April.

While ADP is not an accurate reflection of the government data, it did notch down the odds for a good report in the minds of traders.

Economists, however, still expect a fairly strong number, after March's surprisingly sluggish 126,000 nonfarm payrolls. There are 224,000 nonfarm payrolls expected, and the unemployment rate is projected to fall to 5.4 percent, according to Thomson Reuters.

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"What the biggest single predictor of employment is is jobless claims and ADP is a close second," said Joseph LaVorgna, chief economist at Deutsche Bank. But he said he is sticking with his forecast of 225,000.

The wild card in Friday's number could be the average hourly wages. Anything to do with potential wage inflation has caught the market's attention, like last week's surprise 0.7 percent rise in the employment cost index. LaVorgna expects hourly wages to rise by 0.2 percent.

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"There hasn't been much shift in the trend. My guess is you're probably up two-tenths. That's the pattern. One of these months, we're going to see a bigger-than-expected number and some upward revisions," he said. "It's going to happen at some point if the labor market tightens enough. They're going to bid wages up."

Markets are focused on the wage number, in some ways even more than the overall nonfarm payrolls since wage inflation is seen as one thing that could get the Fed to move toward hiking rates.

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The first quarter turned out much weaker than expected, and economists now see a contraction of about 0.4 percent in first-quarter GDP when revisions are reported later this month. "If it's a weak number ... then people are going to question the extent of the Q2 snapback. I have to tell you now, I'm not looking for a major snapback, not compared to last year," he said.

LaVorgna said he expects growth in the mid 2 percent range but it should pick up later in the year.

"I don't think we'll be negative two quarters in a row, or close to zero. I don't see a recession on the horizon. We're being hit by the big drop in energy capex, the port strike has hurt and the dollar. Those things are likely to keep growth in Q2 lower than last year and lower than Q3," said LaVorgna.

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Ethan Harris, co-head of global economics research at Bank of America Merrill Lynch, said he expects to see 235,000 nonfarm payrolls and an unemployment rate of 5.4 percent. He also ratcheted down his forecast for second-quarter growth recently to 2.5 percent from 3.5 percent.

"We're basically looking for a makeup number," said Harris. "If you look at the broad tone of the labor market data, it looks quite healthy. It kind of stands out. Jobless claims remain extremely low. Survey-type measures suggest healthy growth. The job market has sailed through the soft patch pretty well. We're expecting a number that is kind of bounce back."

Harris, however, said there is some underlying weakness in the economy that isn't just from weather or other temporary factors like the port strike. He expects improvement by the second half, but weakness could linger in the current quarter.

"We do think the dollar move has had a bigger impact on growth than we thought. We're also conceding to some degree that the oil price impact is having more of a mixed impact rather than a positive impact on growth. We think the shock to the mining sector matches the stimulus to the consumer from lower oil prices. While historically, the consumer response is bigger, when oil prices collapse," Harris said.